resistance to rotation, of crank durring short blk assembly

grumpyvette

Administrator
Staff member
Ok youve just installed your crankshaft in the engine block, with new main bearings and everything's well coated with assembly lube,and oil, and youve torqued down the main caps to spec. in at least three stages, and then gone back and rechecked the studs or bolts per the manufacturers instructions, but you have yet to install the pistons and rods, OK, its time to check the rotational resistance at the first stage, while your assembling the engine on the engine stand.
the lubed crank shaft will take a bit more effort to start it rotating than it takes to keep it rotating, as the surface tension and lube shear takes a bit of effort to get it rotating, thats one reason the torque beam style torque wrench is preferred too check the resistance , as you get to see both starting and rotational resistance on the wrench scale, rather than the click style torque wrenches design for verifying the rotational resistance, and be aware that the resistance should NOT significantly change as the crank shaft rotates through its full 360 degrees, if it does it may indicate a block that needs to be line honed to cure a slight block warp- age issue or a bent crankshaft, a dial indicator and an accurate bore gauge and a good solid stand for the indicator can help you locate the cause.
theres zero doubt you can build some of the more common SBC and BBC engines with either a mix of O.E.M. and and aftermarket components,
BE AWARE NOT ALL POTENTIAL PARTS COMBOS ARE COMPATIBLE
or go with just aftermarket components through out.. It should be obvious that you'll need to do some research , and calculations on,
rod length, bearing clearances, compression height, compression ratio, quench, and valve train geometry,intended port flow, valve lift,
and carefully verify the clearance , and valve train geometry issues before ordering components, and during the actually assembly.



https://www.amazon.com/dp/B06VXC1FPL/ref=nav_timeline_asin?_encoding=UTF8&psc=1

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https://garage.grumpysperformance.com/index.php?threads/rotating-assembly-bearings.9527/#post-35037

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as to the rotational smoothness, be aware that, all assembly lubes and oil on blocks bore the rings ride over and all bearing surfaces, coated with oil and assembly lube provide a surface shear tension that must be broken before the crank turns,
so its not un-usually for the rotating assembly after the pistons and rings are installed, too require lets say 35 ft lbs to get the assembly too start too spin ,but only 15-26 ft lbs to keep in rotating , (low tension rings provide less drag) you can generally call the piston ring manufacturers and they should know approximately what torque reading on the crank snout, a socket and a torque wrench will require to have the engine assembly rotate with their rings installed.
a crank snout, turning socket, but if that short block assembly, takes over 35-40 ft lbs too start it rotating, once its assembled without cylinder heads attached, you've got serious issues, like cam lobe to connecting roods hitting or a connecting rod facing the wrong way on the crank journal, or the wrong size bearings, or the crank journals not the right size, badly polished or not round
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that's why you'll need a torque beam deflection torque wrench to check that

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https://www.amazon.com/Presa-Drive-...ocphy=9012039&hvtargid=pla-669567243785&psc=1

read the labels and load rates carefully before ordering they make inch lb, ft lb versions
1/4",
3/8"
and 1/2"

drive versions
and having an inch lb rated one helps at times $25 on amazon
https://www.amazon.com/Neiko-03727A...ocphy=9012039&hvtargid=pla-572951906812&psc=1

https://www.ebay.com/itm/224242691491?epid=23014633155&_trkparms=ispr=1&hash=item3435e7eda3:g:sBkAAOSw5MFfuDZS&amdata=enc:AQAGAAACoPYe5NmHp%2B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSvtkx670Z0mbyfWqmxLFLYbSgftsPKn4P4%2BuyGMgnhW%2FjIce0dpW9M3RoBZspmh1OP12%2B1VAxoUJJj3RoXfTi%2BdPDYwWVpZhnEHOtxRJrO9BgZbW7EgR6P7ToLFxxssR3y9JK0MrcC1gFkn3SW32QlRm1jVDvf75zsqK4K6a3ZYjn8qwXzUYq6h4garZZxJfbfur3C7bxYsXM6Kd0RP%2Bc1qcqgfVJHBlQgVk4udvEWA36jrjTVJl5%2BCY4o1Ivq4bl7iQqsi7Hf9CMDhs1uIRQNOVZaGYqWg9k4J0UBWdzz8l8X%2FOqd9t3DRpXca5J9mjp65pFUANhTN3TfDEtTpSfCkWmlHnqMmYCOvLSwvD1QZMXkSF0aOKRqnGjBtvV0xFal9s9EMVlX8gRTesUivsA%2FodQ%2FlEYPwFdqVXGP1WdDLW4J90gTGRKzasKw%2FOHt7XrubOgzy515noBgagP9s2M1iGfVGLK2dXotGyaTVcSbvCHNSmbSUvaKVX7Jm7hgX3UZIvrnEYFwbpAec4a0%2BqRPqov5SRFpkQ0DGE9tAvXszC8xwzF9%2F%2FxSK%2FPmvpoJ%2FxGmwoio1ZR88UMdq6GHkjzFQIpQE946bHSep0BzmPBPXyILyvAcxWgs1vPcytjTHBLwAMI0lLADbjgWGGJUMAl8nR2wLczSCeJC7Sd5lIfZ%2FPNxz8aB0qf73TtmocTHjhkcVWW3C0bmckieELPrUXPfLp6ltQmqHsGXDFoITaQRs0mPFQ4TRBoUyYcGtfrS8V8XHcQ0TZtCtqoni0tUGwbdHFKQGYpD%2FFFTpEYitoFjODdATrumb5yl7bb5fAiIRVou6oUBD75feDSqdDpB7G23g%3D%3D|ampid:pL_CLK|clp:2334524

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Don,t forget too use a large rubber, leather or plastic mallet, lead hammer to gently beat the crank seated in the bearings, both forward and aft in the block several times , too seat the thrust bearing,
and of course use a dial indicator and plasti-gauge to verify clearances and too check clearances.
I'd alsp point out that all the main caps will need to be torqued in place in at least three stages to allow the block stress to disapate and equalize as the main caps are seated to the block and it helps to go back over the main cap bolts starting at the center and working outwards in a spiral as the caps are tightened at each torque stage.

YES READING LINKS WILL HELP A GREAT DEAL
http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-68861


http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

http://garage.grumpysperformance.co...ed-holes-in-bearings-shells.10750/#post-53298

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-44530


http://garage.grumpysperformance.com/index.php?threads/which-torque-wrench.342/#post-10864

SKIPPING READING THE LINKS IS GENERALLY GOING TO BE A MISTAKE
http://www.superchevy.com/how-to/engines-drivetrain/4380-bearing-clearance-info/

https://www.chevyhardcore.com/tech-...ies-measuring-and-setting-bearing-clearances/

https://www.chevydiy.com/pre-assembly-guide-build-chevy-small-block-engines/

http://knowhow.napaonline.com/know-notes-measure-engine-bearing-clearance/

https://www.mahle-aftermarket.com/media/local-media-north-america/pdfs-&-thumbnails/cl77-1-205r.pdf

http://www.superchevy.com/how-to/engines-drivetrain/0707ch-main-bearing-clearance/

https://www.enginebuildermag.com/2013/03/bearing-clearances/

https://blog.k1technologies.com/how-to-check-bearing-clearances


if your experiencing issues and the crank won,t rotate in the main journals very smoothly , STOP and find out WHY or take the block and crank to a trusted local machine shop, further assembly will just cause problems with long term durability if the basics are not correct! REMEMBER YOUR BLOCK MAY NEED TO BE LINE HONED OR THE CRANK MAY BE BENT OR OUT OF DIMENTIONAL SPECS,THIS NEEDS TO BE VERIFIED AND IF REQUIRED, CORRECTED
theres at least a few hours of very worth while , and quite useful reading in this thread and links that will prevent you wasting time and money, keep in mind the sub links contain a huge wealth of additional info youll need
what seems to be over-looked in many engine builds is simply the fact you'll almost always DEEPLY regret jumping into the engine build with both feet and waving your check book as you sink ever deeper into piles of parts receipts and machine shop bills, rather than stepping back with a legal pad, and a calculator and listing in minute detail exactly what you want to accomplish, and taking the time and effort too list and check out in detail what each machine shop procedure costs, why its required and how much each components costs, what your options are and how each component will add too or benefit the completed combo (or in some cases cause you time and grief)
stepping back and thinking things through in detail and listing the cost and potential problems and finding the solutions BEFORE you dive into the process may be a lot less fun, but in the long term its sure to cost less and result in a far better finished project!

you might be amazed at what a couple hours research into the subject will do to help you build a much more durable engine, and actually reading thru links and sub-links and asking questions helps a great deal

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https://www.carshopinc.com/product_info.php/products_id/49347/SPG1-12
http://garage.grumpysperformance.co...ting-rod-tools-than-some-guys-may-want.16414/
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http://garage.grumpysperformance.co...ting-resistance-to-look-for.11312/#post-51472
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yes I use both micrometers and snap gauges and cross check with plasti-gauge

and yes when you compare the crushed width of the plasti-gauge youll find it rarely falls as an exact match to the bar chart tape that is packaged with it so you can judge clearance based on crush width
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

http://garage.grumpysperformance.co...piston-to-bore-clearance-on-your-block.14251/
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OBVIOUSLY YOULL NEED A TOOL TOO CHECK ROTATIONAL RESISTANCE,

sears sells them for about $20
home depot for $15

http://www.homedepot.com/p/Powerbui...e-Torque-Wrench-644044/203116749?N=5yc1vZc6ev

http://www.sears.com/craftsman-3-8-...999000&pla=&kispla=00932999000P&mktRedirect=y


http://garage.grumpysperformance.com/index.php?threads/bolts-a-bit-of-useful-info.4868/#post-13372

THIS BEAM STYLE TORQUE WRENCH IS THE TYPE TORQUE WRENCH YOU WANT TO CHECK ROTATIONAL RESISTANCE, these come in at least three torque ranges
for checking the rotational resistance you'll want the lower rated version, that reads 0-75 ft lbs or in inch lbs

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BUT NOT WHAT YOULL USE TO TIGHTEN HEAD BOLTS

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if your SBC engine requires over about 30 ft lbs to get it started rotating,
or over about 25 ft lbs to keep it rotating,
youve got issues that you need to look into before further assembly
use lots of moly assembly lube on the bearing surfaces
BBC will require about 3- 5 lbs more effort, on each point
(starting and keeping it rotating, once all 8 pistons are installed)
as the rings lap into the bores and bearings seat, the resistance should rather rapidly be reduced a few ft lbs.
BORES should be lightly oiled and bearings coated with assembly lube.


http://www.4secondsflat.com/Thrust_bearing_failures.html

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/

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keep in mind the assembly lube or even oil on the bearing surfaces has a surface shear limit,
that why the crank is harder to start rotating but the required effort to keep it spinning is significantly lower,
your initial effort to twist the crank must break that surface tension on the lube,
once its sheared the lube forms a lubricating layer and metal to metal contact is prevented as the lube forms a barrier layer

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NEVER GUESS, DEAL IN PROVEN FACT!
Id get out the plasti-gauge and check clearances, don,t guess , know exactly what your dealing with!
if the clearance falls in spec and the bearings look decent they can be re-used, but its foolish to do so if they look overly dirty, worn or don't have the correct clearances
lots of moly assembly lube and spraying any potential moving contact surface with moly spray (like bearings ,lifters rockers) and liberal use of moly assembly lube during the break-in process helps reduce wear issues


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pre-spraying all bearing and valve train components with a moly based spray, helps embed micro moly lubricants in the metallic surface micro fissures , a good paste lube like cranes assembly lube over the spray surface helps insure a good lubricant surface coating, that is far stronger than just the ZINC and PHOSPHATES in oil
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Take the effort and time too CAREFULLY.. read links and SUB LINKS,
THIS is almost mandatory on this web site!

if you want all available useful & related info
http://garage.grumpysperformance.co...earances-and-journal-surface.9955/#post-38385

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/#post-26440


http://garage.grumpysperformance.co...hrust-bearing-failure-info-related-info.1138/


http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-72126

http://garage.grumpysperformance.com/index.php?threads/can-you-reuse-bearings.5544/

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/#post-7077

http://garage.grumpysperformance.co...shaft-journal-surface-finnish.2728/#post-7079


https://www.mahle-aftermarket.com/m...b-2-1114-engine-bearing-failures-brochure.pdf

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-68194

http://garage.grumpysperformance.com/index.php?threads/causes-of-bearing-failure.2727/#post-13056

http://garage.grumpysperformance.com/index.php?threads/don-t-beat-that-damper.83/#post-14101

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/#post-10925

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/assembly-lube-summary.6352/#post-68508

http://garage.grumpysperformance.co...ear-articles-you-need-to-read.282/#post-57371

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I generally use CLEVITE (H) bearings as they have a bit more edge to crank journal edge radias clearance for the bearing shell to crank counter weight clearances
With the crank shaft alone in the main bearings, any inconsistency in the assembly lube thickness, or journal surface finish could and probably will cause a difference in rotational resistance or drag, if it spins fairly easily with a couple fingers on the crank snout with all the mains torqued down and your plastic-gauge checks and micrometers say the bearing clearances are correct your going to be fine, I generally look to have less than 5 ft lbs resistance , on keeping it rotating, once it starts to move, a properly installed strait crank in a properly honed set of main caps with properly clearances main cap bearings well coated with a 50%/50% mix of assembly lube and marvel mystery oil on the bearing crank surfaces and less than 10 lbs to get it to start rotating as the surface tension of most assembly lubes will resist rotation until it starts to rotate, then the resistance to rotation drops off rapidly,
on a newly rebuilt engine the SHORT BLOCK (no heads installed) and with the bearings and cylinder bores oil coated, it should require LESS than 40ft lbs to get rotating and less to keep it rotating, a crank ALONE installed in the correctly tightened main caps should require LESS than 10 lbs to start rotating and far less to keep spinning.
a used engine will develop a bit looser clearances and require LESS force to rotate after the heads are removed.
on a racing engine the crank alone can easily be spun in the main bearings with your fingers and over about 25-28 lbs resistance when using low drag rings usually indicates a problem
a used engine will develop a bit looser clearances and require LESS force to rotate after the heads are removed.


yes having an accurate torque wrench is mandatory when you build an engine, yes having the piston to bore clearance, ring end gap and bearing clearances correct helps a great deal, and yes low tension rings DO tend to reduce the resistance to rotation, and yes, some assembly lubes DO make the engine a bit harder to start the rotation.
obviously a slightly bent crank, inconsistent bearing clearances, non-round crank journals , rough polish surfaces on journals or a block that needs to be line honed or a bent cam or tight cam bearing journals or improper bearing clearance or dry bearing surfaces tend to increase resistance.
IF your engine resists rotation to a higher torque load rate
FIND OUT WHATS BINDING BEFORE PROCEEDING FURTHER, you sure won,t be the first guy to have installed something incorrectly or had the wrong clearance's but catch it BEFORE proceeding further
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HUSKY $88 (worked rather well, over all I was pleased)

http://www.homedepot.com/p/Husky-1-2-in-Click-Torque-Wrench-H2DTW/202916180?N=5yc1vZc6ev

CONNECTING ROD SIDE CLEARANCE AND THRUST BEARING CLEARANCES MUST BE CORRECT.
CONNECTING RODS AND PISTONS MUST FACE THE CORRECT DIRECTION AND RING END GAPS MUST BE CORRECT AS WELL AS BEARING CLEARANCES, and THE OIL PUMP MOUNT STUD MUST NOT TOUCH THE REAR MAIN BEARING SHELL


now once you add all the connecting rods, pistons and rings obviously resistance to rotation will increase as rings slide along bore walls and you've added rod bearings, Keeping in mind that we are discussing a short block with no heads installed yet and rings riding on well oiled cylinder walls, that should require less than 40 ft lbs to spin, less than 30 lbs of resistance is ideal, because an engine turns more easily with the heads removed or the spark plugs removed.

a crank bye it self ,sitting in a properly machined block with the bearings in place, having been coated with a decent assembly lube, (I generally mix CRANE CAMS ASSEMBLY LUBE WITH MARVEL MYSTERY OIL IN ABOUT A 50%/50% mix on bearings) and the main caps torqued in place should require no more that 10 ft lbs to start to spin (MAXIMUM) and in most cases noticeably less to keep it spinning, in-fact most are easily spun with finger pressure alone.
if it takes more than 10 ft lbs somethings either not machined correctly or your clearances or lube are wrong.
after you add the rods and pistons with the rings its resistance to rotation obviously increases but should still be UNDER 40 ft lbs to spin an assembled short block,If your carefully checking clearances you should see a minimal increase in resistance to the crank rotation, during assembly, as each piston assembly is added and torqued into place as ring drag increases resistance but the bearings should add little or any drag if properly sized and lubed.
obviously youll want to check the piston to bore clearance at several locations along the circumference of the bore to piston clearance, and check the blocks cylinder bore for consistent diam. and the bore being truly round in shape and but don,t forget to check the piston ring groove back clearance in the ring grooves and the ring end gaps plus look for piston pin bind in the piston pin bore, look for rod journals that are tapered or out of round and connecting rods with a big end thats not round or bearing that are not consistent in diameter across the bearing bore, but Ive also occasionally seen guys try to install rods without checking side clearance or who failed to get the correct side of the connecting rods facing each other or guys using rod bearings that didn,t have the correct edge bevel to clear the journal s radias edge, usually the narrower clevite (H) series have extra clearance

Get out the torque wrench and with the damper bolt installed turn the crank,and while its yet to have the rods and pistons installed, and its lying in its bearings, IT SHOULD TAKE ABOUT 10-12 ft lbs OR LESS to get it moving, and LESS than 10 lbs to keep it moving.
EVEN IN NEW MAIN BEARINGS, it should REQUIRE EVEN LESS ONCE IT LAPS INTO PLACE WITH THE ASSEMBLY LUBE

IF it takes more force theres a clearance issue or the crank or block needs to be checked carefully for straightness, journal tapper and roundness and surface finish and the bearings need to be checked for clearance and proper installation and crush,remember if it won,t turn or spin easily STOP RIGHT THERE and find out why! don,t forget to check the TRUST BEARING fore and aft movement/CLEARANCE
once youve installed EACH connecting rod, you'll want to do the test again, remember each piston with its rings adds drag, AND YOU NEED TO VERIFY THE RING GAPS AND PISTON GROVE DEPTH AND CLEARANCE TO ALLOW THE RINGS TO SLIDE BACK INTO THE GROOVES, but in a well oiled cylinder,its not going to add a huge increase, in drag, as the rings ride on an oil film that prevents incorrect full surface physical contact, between the ring face and bore walls, and the bore surface will lap into the rings and vice versa during the break-in process.
IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections the amounts not that great, ideally each one installed adds a bit of resistance but at no time should the short block take over 40 ft lbs ABSOLUTE MAXIMUM to start it spinning,and LESS than 20 lbs to keep it moving, even with all the rings and pistons installed,yes you need to verify the bearing clearances during assembly and IT SHOULD take between 20lbs-25 lbs to start it spinning if the clearances are correct! and LESS than 20 lbs to keep it moving
IF it takes over 40 ft lbs to get it rotating ,youll need too DISASSEMBLE and FIND OUT WHY!

when you get the crank polished take the time and effort to clean out any cross drill oil feed passages and to very carefully de-burr the passage opening edges, as this is a very commonly overlooked issue, below is what at first looks like a perfectly polished crank, with oil feed passages to the rod bearings, but the deep scratches the oil feed passage openings left in the rod bearing surfaces bare witness, after a single rotation, during a trial assembly show they are HARDLY burr free or ready for use, and obviously he failed to check each rod bearing during the assembly process, and probably ignored , what was very likely un-even or rather excessive resistance to the crank rotation. which should never exceed about 40 ft lbs even with all 8 rod bearings and pistons installed

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http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/

http://garage.grumpysperformance.co...n-my-3rd-rear-main-seal-bbc.11084/#post-49384

http://garage.grumpysperformance.com/index.php?threads/replacing-a-gen1-rear-main-seal.474/#post-585

http://garage.grumpysperformance.co...gine-project-dart-shp.3814/page-12#post-17457

http://garage.grumpysperformance.co...od-rod-length-too-stroke-info.510/#post-10311

READ THIS LINKED INFO

Common assembly clearances
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GET THE RING END GAP TOO TIGHT AND WHEN THE RINGS EXPAND WITH ENGINE HEAT THE ENDS TOUCH THE RINGS LOCK IN THE BORE AND THE PISTON LANDS SHEAR OFFGET THE GAP A BIT TOO LARGE AND YOU MIGHT BURN A BIT MORE OIL OR LOOSE SOME COMPRESSION, YOU'LL SEE A CHART LATER IN THE THREAD, BUT GENERALLY YOU'LL WANT .0045-.0065 PER INCH OF BORE DIAM. FOR A RING END GAP

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(ALWAYS consult your piston manufacturer for recommended clearances. Many pistons require a tighter bore)

Piston to bore 0.0055 - 0.0065" ( measured at centerline of wrist pin, perpendicular to pin)


Piston ring gap MINIMUM end clearances Top 0.022"
2nd 0.016"
Oil 0.016"

Wrist pin 0.0006 - 0.0008" in piston, 0.0008 - 0.0010" in rod for full floating pin (End play 0.0 - 0.005"

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" , 0.005 - 0.007 crankshaft end play

Piston to head clearance 0.035 MINIMUM including gasket (steel rods), 0.060" MINIMUM aluminum rods

Valve to piston clearance MINIMUM 0.020" exhaust , 0.010" intake NO VALVE FLOAT
Recommended: 0.080 intake, 0.100 Exhaust (steel rods) 0.100 intake, 0.120 Exhaust aluminum rods
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Ive got a full set of Mitutoyo mics 1" 2" 3" 4" 5" I paid several hundred dollars for,
and a cheap duplicate set from northern tool mics along with half a dozen different digital calipers and so far they all are consistent enough that theres not been any effective difference.
now I fully agree theres a very noticeable difference in quality , that's not debatable,if you need to know that last couple ten thousands of an inch your wasting any money spent at HF MICROMETERS , the accuracy is just not available but if your just measuring something like a piston ring thickness, or crank journal diam. and getting within 2 ten thousands plus or minus is ok, they all work well enough, and for most hobby level builders I think thats true! especially when I see guys installing rings right out of the box without checking end gaps, or even using plasti-gauge to check bearing clearances
and yes I constantly cross check them against each other, in fact I generally use several mics and a digital caliper during engine assembly, and constantly recheck against the precision gauge blocks and feeler gauges
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most piston compression rings have a dot on the upper surface to indicate the side designed to face the top of the piston
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ideally the pressure above the piston gets behind the top compression ring and increases the force holding the ring face to the bore surface, noticeably more than the ring tension alone can do.
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http://www.enginelabs.com/engine-tech/e ... ng-tension
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If you put together a stock 400 Chevy, and put standard tension rings in it, it’s probably going to take about 30 to 35 foot-pounds of torque to turn that shortblock,” Massingill said. “If you put it together with the rings that we utilize [for the Engine Masters Competition], it’s going to take about eight or nine pounds. Can you imagine, at 7,000 or 8,000 rpm, the difference that that is? It can easily be 30-35 horsepower.”
BTW

IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections

remember that when you go to re-install the compressed piston rings, and piston in the engine block,bores that dunking the piston in MARVEL MYSTERY OIL , just before, its slid into the ring compressor will coat the rings and bore contact areas enough to prevent many small problems that insufficient lube might case

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bearings AND connecting rods have an inner facing side and outer side the inner side facing the matching rod has far less edge clearance because they don,t need the radias that is required for the edge of the crank journals

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https://www.youtube.com/watch?v=8GVQiYAVSDQ

btw
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http://www.tooltopia.com/fowler-72-646-300.aspx


https://www.youtube.com/watch?v=LcOHsZxuqAM&t=23s

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heres the good assembly lube (I usually add about 10% oil too the assembly lube,to get it easy to smear on surfaces during the assembly process)
http://www.cranecams.com/index.php?show ... l=2&prt=15
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Ive generally found the H-series bearings are the best choice
MORE USEFUL INFO
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BE 100% SURE that the oil pump bolt or STUD doesn,t protrude past the inner main cap surface , because if it bears on the rear main bearing shell it will almost always result in a quickly failed rear bearing
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failure to use the correct stud, bolt or nut,
OR OIL PUMP FOR THE APPLICATION,
or check clearances when mounting an oil pump,
can cause problems
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ONE RATHER COMMON MISTAKE IS USING THE WRONG OIL PUMP STUD OR BOLT TO MOUNT THE OIL PUMP AS IF EITHER EXTENDS THRU THE REAR MAIN CAP IT CAN AND WILL BIND ON THE BEARING AND LOCK OR RESTRICT, SMOOTH ROTATION
http://engineparts.com/techbulletins/CL77-1-205R.pdf

viewtopic.php?f=50&t=1222

http://garage.grumpysperformance.com/index.php?threads/number-stamp-sets.1738/

http://www.chevyhiperformance.com/tech/ ... index.html



http://www.4secondsflat.com/Thrust_bear ... lures.html

http://www.circletrack.com/techarticles ... index.html

http://garage.grumpysperformance.com/index.php?threads/crankshaft-journal-surface-finnish.2728/

http://www.connectingrods.net/connectin ... tretch.php

http://www.circletrack.com/techarticles ... index.html

http://www.circletrack.com/enginetech/1 ... education/

http://engineparts.com/it_bearinginstall.asp

http://www.circletrack.com/enginetech/c ... ce_basics/

http://engineparts.com/it_crankinstall.asp




http://www.chevyhiperformance.com/tech/ ... index.html

the CRANE assembly lube is excellent but IVE used this grease mixed with a bit of mobile 1 oil as a substitute on bearings at times with excellent results
advance auto carries some
http://www.grumpysperformance.com/p1171 ... _large.jpg
http://shop.advanceautoparts.com/productdetail.aspx?MfrCode=VLV&MfrPartNumber=632&CategoryCode=3251

if your well lubed short block won,t spin at under 40 ft lbs once assembled even with high drag rings its a HUGE PROBLEM!
you need to use moly assembly lube
pull ALL the pistons and rods and verify the crank alone takes LESS than 15 lbs to spin, if not start checking clearances, once that's done verify the piston side clearances, then ring end gaps, ring to groove clearances in the pistons and the piston pin to piston pin bore side clearances,then remember the rods have an inner and outer facing side, and the bearings do also in most cases, check rod side clearance and thrust bearing clearance, and when your assembling the pistons & rods to the crank rotate the crank after each ones installed to find any unusual increased drag, a slightly bent rod, or the wrong bearings can add a good deal of drag


one factor to keep in mind is that rods typically have a side that rides against its matched companion and a side thats BEVELED for clearance on the crank journals radias EXAMPLE
rodoil1.jpg

rodoil2.gif

rodoil3.jpg

rodoil4.jpg

oliverrodsr.jpg

notice the top rods non-beveled side that faces the matching rod is up, but on the lower rod the the beveled side that faces the crank counter weight is up on the lower rod

notice how one side of the bearing holding section has a radias (left)(GOES TOWARD CRANK COUNTER WEIGHT) but the opposite sides flush (right) (FACES MATCHED ROD)
you really need to read thru these threads



http://www.circletrack.com/howto/1818/index.html


p117194_image_large.jpg

arp-100-9942_w.jpg

btw spray the bearing and the crank surfaces, and the plastigage with WD40 before you measure clearances and it won,t tend to stick as much
tru3.jpg


tru4.jpg


thr1.jpg

A simple modification to the upper thrust bearing may be beneficial in some engines. Install the upper thrust bearing in the block to determine which thrust face is toward the rear of the engine. Using a small, fine tooth, flat file, increase the amount of chamfer to approximately .040" (1 mm) on the inside diameter edge of the bearing parting line. Carefully file at the centrally located oil groove and stroke the file at an angle toward the rear thrust face only, as shown in the illustration below. It is very important not to contact the bearing surface with the end of the file. The resulting enlarged ID chamfer will allow pressurized engine oil from the pre-existing groove to reach the loaded thrust face. This additional source of oiling will reach the loaded thrust face without passing through the bearing clearance first (direct oiling). Since there may be a load against the rear thrust face, oil flow should be restricted by that load and there should not be a noticeable loss of oil pressure. This modification is not a guaranteed "cure-all". However, the modification should help if all other conditions, such as surface finish, alignment, cleanliness and loading are within required limits.
bearing41.jpg

ThrustBearingModParallel01a.jpg

trustbca.png


WATCH THIS VIDEO
NEVER USE A TORQUE WRENCH LIKE A BREAKER BAR TO LOOSEN BOLTS as it TENDS TO QUICKLY DESTROY ITS ACCURACY & consistency

http://www.youtube.com/watch?v=zgwwOJ0B ... r_embedded



http://www.chevelles.com/forums/showthread.php?t=379622

ONE youve installed the engine in the car, and ASSUMING you've PRE-PRIMED the oil pump and oil runs out of the rockers,if it takes more than 40 ft lbs to get it to turn freely , without the spark plugs installed, or accessory belts on, or the transmission installed, somethings binding or the clearances are wrong, Id start by loosening all the rockers and see if it makes a difference, you would not be the first guy to think everything's adjusted correctly yet have the valves not adjusted correctly

read these threads above

if youve used a quality assembly lube, and have the correct clearances it should require NO MORE than 40 ft lbs of force to start an engine too turn and under 20 ft lbs to keep it spinning, and thats with new rings in a newly honed bore, that effort required should drop rapidly to the point that less than 20 ft lbs are required to spin a short block after its been well oiled and rotated dozens of times.
one factor some new guys over look is that rods and bearings are designed with one side having a bevel that faces the counter weights and a non-bevel edge facing the matched rod


arpultratorque.jpg

In any application where your tightening a nut on a stud , such as on the outer threaded ends of main cap studs or head bolt studs,or rod bolts, youll want to use a lube on the threads that gives consistent torque reading from your torque wrench indicating the correct bolt or stud TENSION, oil and MOLY assembly lube and various thread sealants do not always do that,the end in the blocks course threads have thread sealant, the fine threads on the outer end require a totally different lubricant

ringcomp2.jpg

GOOD and VERSITILE

ringcomp3.jpg


WORKS GREAT BUT LIMITED TO A NARROW BORE RANGE AND EXPENSIVE
ringcom1.jpg

ringcom2.jpg

ringcom3.gif

http://www.amazon.com/KD-Tools-850-Diam ... 0002STSMG/
AA1040_.jpg


http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.com/index.php?threads/piston-ring-gaps.2837/#post-7989

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/

http://garage.grumpysperformance.com/index.php?threads/installing-rings-in-piston-grooves.9490/

http://garage.grumpysperformance.co...ng-piston-ring-grooves-and-related-info.1797/

http://garage.grumpysperformance.com/index.php?threads/maximizing-piston-to-bore-ring-seal.3897/

http://garage.grumpysperformance.co...roove-depth-clearance-effects-ring-seal.5454/


this type (ABOVE) handles many applications but the cheap versions are a P.I.T.A. to work with


pro-66767_w.jpg

BTW when you go to buy a ring compressor....this type(ABOVE & BELOW) works far better than the others, but its specific to a very limited range in bore size applications

pro-66766.jpg


http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-66766&N=700+115&autoview=sku

Proform 66766 $31

Tech InformationInstallation Tips


Engine Bearing Installation and Fitting Tips

When measuring bearing measurements, they should always be taken at 90-degrees to the parting line to determine the minimum clearance. If measuring the bearing wall thickness, use a special micrometer with a ball anvil to fit the curvature of the bearing ID. The best way to determine bearing clearance is to measure the bearing ID with the bearings installed in the housing and the bolts torqued to the specified assembly torque. Use a dial bore gauge to measure the bearing ID at 90-degrees to the parting line, then subtract shaft size from bearing ID to determine the clearance. If the dial bore gauge is zeroed at the actual diameter of the crankshaft journal to be installed, the dial bore gauge will then read clearance directly and the subtraction calculation can be eliminated. About .001" clearance per inch of shaft diameter is a good rule of thumb. Increasing that by about .0005" will add a little margin of safety when starting out, especially for rods. Example: .001" X 2.100 = .0021" then add .0005", so starting out set clearance at .0026" for a 2.100 shaft.

If clearance adjustments need to be made, use either an extra clearance part for more clearance or an undersize part for less clearance. It is permissible to mix sizes if less than .001" adjustment in clearance is desired. When mixing sizes for a select fitting: a) never mix parts having more than .0005" difference in wall size; b) and always install the thickest wall shell in the upper position if installing a rod bearing or the lower position if installing a main bearing. When working with a reground shaft, always measure assembled bearing ID's first. Next have a shaft sized to produce the desired clearance since there are no extra clearance parts available for undersize shafts.

When measuring a bearing ID or wall thickness, avoid measuring at the parting line. The diagram illustrates there is a parting line relief machined into nearly all bearing shells. This relief is to allow for any mis-match between upper and lower shells due to tolerance differences, or possibly resulting from cap shift or twist during assembly. To determine bearing wall eccentricity or assembled bearing ID ovality, measure at a point at least 3/8" away from the parting line.

When installing any bearing DO NOT ATTEMPT TO POLISH THE BEARING RUNNING SURFACE WITH ANY TYPE OF ABRASIVE PAD OR PAPER. Bearing overlay layers are extremely soft and thin – typically .0005" on high performance parts. These thin layers can easily be damaged or removed by an abrasive media. Because the overlay layer is electroplated, it may exhibit microscopic plating nodules that make it feel slightly rough. The nodules are the same material as the rest of the plated layer and will quickly be flattened by the shaft. Bearing surfaces can be lightly burnished with solvent and a paper towel if desired.

Arriving at the correct choice of a high performance bearing for any given racing application is much like determining what clearance works best. From past experience, our knowledge of the intended usage and common sense can guide us in making an initial choice. Next, we can fine tune the selection process based on those results. The information given here is intended to aid in the initial selection as well as the fine tuning process.

The following table serves as a brief overview of the features included in each of the special Clevite 77® brand high performance bearing series.
bearingchart.jpg

http://www.stealth316.com/misc/clevite-77-rod-main-bearings.pdf
http://www.scatcrankshafts.com/product-search/

https://www.summitracing.com/parts/sca-6570020

sure the earlier bore size is listed

for those of you un-aware of rod journal sizes

Chevy Smallblock V8 Crankshaft Journal Sizes


Gen.I, "Small Journal"

265...Mains-2.30"-Rods-2.00"
283...Mains-2.30"-Rods-2.00"
302...Mains-2.30"-Rods-2.00"
327...Mains-2.30"-Rods-2.00"


Gen.I, "Medium Journal", includes "Vortec" 305 and 350 thru '98
262...Mains-2.45"-Rods-2.10"
267...Mains-2.45"-Rods-2.10"
302...Mains-2.45"-Rods-2.10"
305...Mains-2.45"-Rods-2.10"
307...Mains-2.45"-Rods-2.10"
327...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"


Gen.I, "Large Journal"
400...Mains-2.65"-rods-2.10"


Non-production Gen.I combination, using Gen.I 400 crank in Gen.I 350 block
383...400 crank, Mains cut to 2.45"-Rods-2.10"


Non-production Gen.I combination, using Gen.I 350 crank in Gen.I 400 block
377..."Spacer" or "thick" main bearings with 350 crank-Rods-2.10"


Gen.II, "Medium Journal", includes "L-99" 265, "LT-1" 350, "LT-4" 350
265...Mains-2.45"-rods-2.10"
305...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"


Non-production Gen.II combination, using Gen.II 265 "L-99" crank in Gen.II 350 block
302...Mains-2.45"-Rods-2.10"


Gen.III, includes '97-2005 "LS-1" Corvette, Firebird, Camaro
345...Mains-2.558"-Rods-2.10"


Corvette "ZR-1", DOHC, "LT-5"
350...Mains-2.76"-Rods-2.10"
narrow bearings have beveled edges to prevent the edge of the crank journal radias touching the bearing, h series are beveled edge bearings designed for higher loads so they are a bit harder
70-95 454 Chevy Clevite performance main bearing set. Clevite 77 "H" Series bearings have a medium level of eccentricity, high crush, and rod bearings have a hardened steel back and thin overlay. These bearings also have enlarged chamfers for greater carankshaft fillet clearance and are made without flash plating for better seating. Use "H" Series bearings with crankshafts that have oversize fillets and where engines run in medium to high RPM range.

bearingoffset2.jpg


http://garage.grumpysperformance.co...ng-piston-pin-height-compression-height.5064/

http://garage.grumpysperformance.co...n-wrist-pins-one-really-over-looked-part.978/


if you find the rotating assembly is more difficult to rotate than you expected, you may want to verify some clearance issues that get over looked at times,
theres also some, other potential issues,
theres a slight potential for the piston wrist pins too not rotate effortlessly in the piston pin bores ,

that may add to the difficulty in rotating the assembly in the block.
the piston rings must have vertical and back clearance in the piston ring grooves

ringslack.jpg


RingsSM2.png


art.png

Piston Ring Groove Clearance
Pistons are grooved to fit rings that seal the cylinder’s compression and allow for lubrication of the cylinder walls. Piston rings come in a set. There are two compression rings. The top ring is affected by the most cylinder compression pressures. The second compression ring reinforces the top ring. The third ring down is the oil ring. It controls lubrication between the piston and cylinder bore.

piston-ring-groove-clearance.png

Place the new ring into the top piston groove, and then place a feeler gauge into the gap between the new ring and the upper land. Move around the pistons groove and obtain a few measurements. Compare this reading to specifications. If this reading is too much and the gap is too large, the piston must be replaced. The top ring takes the most compression. This causes the ring to slap against and wear the lands in the piston groove.
rings-fl.jpg


RingInstallation1.jpg


ringslack.jpg


and of course the pistons must have the correct piston too bore clearance. and connecting rod can only be installed facing one direction
bearingoffset1r.jpg

Picture106r.jpg

bearingoffset1r.jpg

you can use all the precision measuring tools you may have but the truth is always evident in cross checking with plasti-gauge
www.summitracing.com

Clevite Engine Parts MPG-1 Clevite 77 Plastigage | Summit Racing

Free Shipping - Clevite 77 Plastigage with qualifying orders of $99. Shop Plastigage at Summit Racing.
www.summitracing.com

bearings and oil flow

Bearings and oil flow viewtopic.php?f=53&t=88 http://www.babcox.com/editorial/us/us90126.htm http://www.insightservices.net/testoil/ ... cation.htm http://www.thirskauto.net/BearingPics.html http://micapeak.com/info/oiled.html http://www.unofficialbmw.com/all/misc/all_oilfaq.html...
garage.grumpysperformance.com

Precision measuring tools

I’m looking for the best quality precision tools on a limited budget (i.e. I don't want to pay $300 for one mic). I plan on building the occasional small- & big-block Chevy (more than one, less than 1000). Names that come up on the limited results I’ve found on the web include Starrett...
garage.grumpysperformance.com

lining up oil feed holes in bearings shells

I just got an e-mail asking what to do if you find that the blocks oil feed passage holes don,t line up exactly right with the holes in the oil feed holes in bearings shells? paint, marker etc. tends to wash off, you really should lightly die stamp the main caps...
garage.grumpysperformance.com

assembling and installing connecting rods/pistons

look closely at the connecting rods one edge of the main bearing are is beveled noticeably more than the other that beveled side faces away from the rod its paired with because it matches the slight radiased bevel of the crank journal many builder class pistons are designed to go in, in either...
garage.grumpysperformance.com

assembling and installing connecting rods/pistons

He Measured .0004" - 4/10,000 th of an inch #5 MAIN CAP BORE DISTORTION TORQUED DOWN TO SPECS WITH THE OIL PUMP ON. I DON'T.LIKE IT. IT SHOULD BE +/- .0001" TOLERANCE. +/- .0002" INCH MAX.
garage.grumpysperformance.com

matching parts and a logical plan

I just had a rather long and detailed discussion with a guy who it was all too obvious ,was basically just, trying to get me to give him a detailed list of engine components to build his engine. one of the main secrets , too building a really effective combo is to match the engine and drive...
garage.grumpysperformance.com
I use both micrometers and snap gauges and cross check with plasti-gauge
and yes when you compare the crushed width of the plasti-gauge youll find it rarely falls as an exact match to the bar chart tape that is packaged with it so you can judge clearance based on crush width
plastigty1.jpg



http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/
plas1v.jpg

plas2v.jpg



bearing1a.jpg


bearing2a.jpg


bearing3a.jpg



as a general rule you select .001 bearing clearance for every inch of bearing journal diameter,
Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" for most engines ( 0.020-0.025 bearing clearance on small blocks, .025-.027 bearing clearance is about ideal, on big blocks ), 0.005 - 0.007 crankshaft end play

http://garage.grumpysperformance.co...ng-clearances-engine-builders-magazine.11965/


http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/
 
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Re: resistance to rotation

youll need ring assembly info also

and never beat the damper onto the crank, use the correct tool
71061744.jpg


look at the picture carefully
the small 7/16 thread ,on the tool threads into the crank, the damper slips over the tool, the large washer style bearing slips over the tool followed by the solid washer followed by the large nut that threads on the tool, the back of the tool is normally a 9/16 or 5/8 hex this is held with a box end wrench to keep the engine from turning, the large nut is usually a 1 1/8" nut and it is tightened with an open end 1 1/8" wrench or a adjustable wrench against the two washers drawing the damper onto the crank snout! lube the threads on the tool, the inside of the damper and crank snout with oil before starting. the damper will normally slide on about 1/4 of the way bye hand then the tool is needed to draw the damper on the last 3/4 of the distance, don,t over tighten the tool the 7/16" thread will snap off in the crank after the damper bottoms out on the lower timing gear if you do!,
NEVER USE A HAMMER AND BLOCK OF WOOD TO DRIVE THE DAMPER ON, YES THOUSANDS OF GUYS THINK THEY DID IT WITHOUT ANY PROBLEMS BUT...
IT WILL DAMAGE THE THRUST BEARING CLEARANCES,
IT CAN BREAK THE ELASTOMER TORSION RING ON STOCK DAMPERS
IT CAN CAUSE THE INERTIAL RING ON FLUIDAMPER TO BECOME JAMMED INTERNALLY
IT CAN CAUSE THE DAMPER TO FAIL.
IF THE DAMPER FAILS THE CRANK WILL EVENTUALLY BE DAMMAGED
IT GREATLY STRESSES THE CRANK SHAFT
IT CAN DAMAGE THE CRANKS TRANSMISSION PILOT BEARING
IT CAN DAMAGE THE TRANSNSMISSION
ALMOST EVERY TYPE OF DAMAGE IS NOT SOMETHING THAT SHOWS UP RIGHT AWAY, BUT IT WILL DAMAGE THE PARTS LISTED AND THERES THOUSANDS OF GUYS THAT ARE WONDERING WHY THOSE PARTS FAILED 6-24 MONTHs LATER WITH NO CLUE AS TO THE CAUSE!
ASK YOURSELF THIS QUESTION, IF CRANKSHAFTS THAT ARE A FEW THOUSANDS OUT OF LINE I.E. NOT PERFECTLY STRAIT ARE BENT/STRAITEN WITH A LEAD HAMMER BY CRANK MANUFACTURES (and yes thats how its done) AND CRANKS THAT ARE DROPPED ON A CONCRETE FLoOR SOMETIMES BEND SLIGHTLY ,(happens all the time) WHAT MAKES YOU THINK THAT BEATING ON THEM WITH A HAMMER AND A BLOCK OF WOOD WONT DAMAGE THEM? AND WHILE WERE AT IT WHAT WOULD YOU DO TO SOME GUY YOU CAUGHT BEATING ON YOUR ENGINE BLOCK WITH A HAMMER? WELL WHAT DO YOU THINK THE CRANKS DOING TO YOUR MAIN CAPS WHEN YOU BEAT ON THE CRANK? PROPERLY USED THAT INSTALLATION TOOL CAN EXERT OVER 15 TONS OF PRESSURE TO SLIDE THE DAMPER ON, IF IT WONT SLIDE ON, THERES A PROBLEM! FIND IT AND FIX IT .....DON,T BEAT ON THE DAMPER/CRANK

having a few tools designed to easily rotate the engine on hand helps
crank rotators
77866782.jpg


BTW I assume you gentlemen do know theres
even a correct and very inexpensive tool for spinning it from the flex-plate or flywheel,
once the cylinder heads are installed,
so your not stressing the damper retention bolt spinning the engine over manually,


https://www.summitracing.com/parts/wmr-w80510/overview/

https://www.summitracing.com/parts/sum-900178/overview/
55580530.jpg



http://www.jegs.com/i/JEGS/555/80743/10002/-1

http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&Ntk=all&Jnar=0&itemPerPage=90&Ne=1+2+3+13+1147708&searchTerm=55580530

CHECKING TRUST BEARING CLEARANCE
THIS BEAM STYLE TORQUE WRENCH IS THE TYPE TORQUE WRENCH YOU WANT TO CHECK ROTATIONAL RESISTANCE
beam_torque_wrench.jpg


ID SUGGEST YOU KNOCK THE CRANK FRONT TO BACK IN BOTH DIRECTIONS WITH A PLASTIC DEAD BLOW HAMMER SEVERAL TIMES TOO SEAT THE THRUST BEARING BEFORE MEASURING CLEARANCE WITH A DIAL INDICATOR ON THE CRANK SNOUT! (IDEALLY .007-.010)
you can increase thrust bearing clearance, a couple thousands if required, by polishing the thrust bearing to crank surface on a sheet of wet, fine grit, sand paper ,on a sheet of glass, with 1000 grit wet/dry sand paper in a figure 8 pattern obviously clean the bearing carefully befor re-installing it!

thr1.jpg

ALWAYS PAY ATTENTION TO THE PICTURES AND LINKS AND SUB LINKS
NOTICE NO CONNECTING RODS ON THE CRANK WHILE VERIFYING THRUST BEARING CLEARANCES

http://www.harborfreight.com/4-lb-neon-orange-dead-blow-hammer-69004.html
every engine builder needs a plastic dead blow hammer, After torquing the main caps in place and before installing connecting rods you'll need to drive the crank back and forward in the main bearing saddles a few times fore and aft, to properly seat the thrust bearing before taking clearance measurements, and only then proceed to the rod & piston install, rotational resistance checks and checking rod side clearance during assembly.

tru2.jpg


tru3.jpg

rodoil1.jpg

rodoil2.gif

rodoil3.jpg

rodoil4.jpg

rodjn1.jpg

rodjn2.jpg


read link
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/page-2#post-90591



tru4.jpg


http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/

http://garage.grumpysperformance.co...gine-project-dart-shp.3814/page-23#post-21571

http://garage.grumpysperformance.co...hrust-bearing-failure-info-related-info.1138/

http://garage.grumpysperformance.com/index.php?threads/causes-of-bearing-failure.2727/#post-13056

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/#post-7077

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/#post-26599

http://garage.grumpysperformance.com/index.php?threads/rotating-assembly-bearings.9527/

http://garage.grumpysperformance.co...g-up-oil-feed-holes-in-bearings-shells.10750/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.co...ank-durring-short-blk-assembly.852/#post-1534

heres a few things to check if your short block rotating assembly seems to be hard to manualy rotate

are the connecting rods installed with the beveled edge facing out on each pair with the bearing installed with the bevel facing out on both the lower and upper rod bearings also?

are you using beveled bearing shells that have the clearance to easily match the cranks throw journal bevels?

what are the bearing clearances? at least use plasti gauge (are they the same checking at 90.120.160 degrees from the first measurement?}

what are the connecting rod side clearances on all 4 pairs (did you verify with a feeler gauge?)?

is the crank strait? has it been turned undersize? if so...on ALL the rods?
on ALL the mains? or on ALL the BEARINGS JOURNALS OR ONLY SOME?

whats the TRUST BEARING CLEARANCE?(did you check with a dial indicator, after knocking the crank forward and back in the bearings a few times with a mallet to seat the thrust bearing)

is the piston side clearance correct?
did you end gap the rings correctly?

are the pistons installed in the correct cylinders? (intake and exhaust notches correctly located to match the cylinder head)

are you POSITIVE each main cap is in the correct location,
and FACING THE CORRECT DIRECTION?

did you use MOLY assembly lube?

did you check EACH INDIVIDUAL RING ON EACH PISTON for ring gap clearance,AND that the rings fit the piston ring slots correctly? are any rings installed in the wrong ring slots (2nd ring in top slot ETC,)or upside down

do the rings have back clearance? in the piston groove

were the cylinders CORRECTLY HONED?

is the cam drive binding?

does the crank contact the windage screen?

does the dipstick tube or dip stick touch the crank at any point?

is the oil pump /cam gear binding?

did you check that the oil pump mounting bolt does NOT contact the back surface of the rear main BEARING under the main cap?

is the block warped, checked carefully?,was it line honed?


are the piston pins centered? do the pistons rotate thru an arc with little resistance, on the piston pins??

are there any lock pins, spirolocs, tru-arcs contacting the cylinder walls?

are you sure the bearing shells are installed correctly and the locating tabs are in the correct slots?
are they the correct bearings for the application? or did you just assume the part guy knew what he was doing?

did you MEASURE or GUESS, did you at least use Plasti-gauge to check clearances and a beam style torque wrench to verify rotational resistance.torque wrench?

did you check EACH AND EVERY journal for tapper and roundness

mcap4z.gif

mcap2.jpg

mcap3.jpg

mcap5.jpg



related
read the links its worth your time and effort
https://www.engineprofessional.com/EPQ3-2020/mobile/index.html#p=16

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-59253


http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-68651

http://garage.grumpysperformance.com/index.php?threads/bits-of-383-info.38/page-2#post-61958

http://garage.grumpysperformance.com/index.php?threads/block-prep.125/

http://garage.grumpysperformance.co...ing-a-383-sbc-combo-planing.12168/#post-58778

http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-55651

http://garage.grumpysperformance.com/index.php?threads/bare-minimum-tools.11026/#post-51823

http://garage.grumpysperformance.com/index.php?threads/parts-prep-cleaning.6255/#post-51146

http://garage.grumpysperformance.com/index.php?threads/383-information-overload.11137/#post-49857


http://garage.grumpysperformance.com/index.php?threads/analyzing-piston-damage.16432/

http://garage.grumpysperformance.com/index.php?threads/big-block-chevy-info.710/#post-49737

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-52466

http://garage.grumpysperformance.co...ting-started-in-the-car-hobby.339/#post-60187
 
Last edited by a moderator:
Re: resistance to rotation, of crank during short block assembly
should obviously be based on use of the correct clearances, and use of assembly lube on the bores and bearing surfaces, use of a strait crank and block thats been line honed if required


check your cranks end play (forward/aft slack in the bearings)

http://members.rennlist.com/v1uhoh/cranksha.htm

http://www.competitionproducts.com/Short-Blocks-Chev-SB/departments/1224/

http://www.tpub.com/content/constructio ... 050_74.htm

http://www.chevyhiperformance.com/tech/ ... index.html

http://books.google.com/books?id=TXEMMg ... &ct=result

http://www.circletrack.com/howto/1815_c ... index.html

http://books.google.com/books?id=1dcXtE ... &ct=result

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/

http://garage.grumpysperformance.com/index.php?threads/main-cap-fit-in-block.5945/#post-18302

http://garage.grumpysperformance.com/index.php?threads/splayed-main-caps.1014/#post-3831

http://garage.grumpysperformance.co...block-cylinder-wall-thickness.976/#post-22976

HERES A PICTURE, main caps are usually cast with a arrow showing the direction they face but seldom number stamped to indicate the correct location in the block and its best to do that during the dis-assembly too insure they go back in the correct location.
cap21.jpg

cap22.jpg

maincapmis.jpg

http://www.harborfreight.com/36-piece-14-in-steel-letternumber-stamping-set-60671.html

333.jpg


its usually standard practice to lightly stamp the outward facing rods and rod caps and main journal caps with the cylinder number or location they will be or are located in and a matched stamped number on the oil pan rail of the block, its also useful to stamp the main caps on one edge and a matched stamped number on the oil pan rail of the block, indicating which direction each main cap faces and its location during the original DIS-assembly process or first engine assembly to prevent potential screw-ups during later builds or refresh builds.
just make the stamped number clearly readable but not deeply stamped as you don,t want to induce potential stress risers that might weaken the connecting rods

stampedrods.jpg

HERES A GREAT DEAL OF INTERESTING RELATED INFO




http://www.summitracing.com/parts/CRN-99004-1/



arp-100-9909_w.jpg

ABOVE FOR BOLT THREADS NOT BEARINGS
marvel.jpg

asl1.jpg

crn-99004-1_w.jpg

P801504.jpg

man-40177_w.jpg

ABOVE FOR BEARINGS, LIFTERS CAM LOBES ETC.
read these links


http://www.summitracing.com/parts/MAN-40177/?rtype=10

http://www.performanceproducts4benz.com ... -lube.html

(btw when using a cylinder head in place style piston stop tool
if your standard strait probe/stop tool is not touching the piston due to the shallow enterance angle

youll want to remove ALL the spark plugs and back off ALL the rockers
on not only cylinder number one ,
but all the cylinders
,
so you can feel the engine as it moves/rotates
yes youll need to adjust valve when your done finding TDC
http://garage.grumpysperformance.com/index.php?threads/adjusting-valves.196/


and make sure the cars not in gear so that the engine can be rotated much more easily when done manually,
this prevents the valves in cylinder number one from opening and removing the other spark plugs greatly reduces resistance due to compression.

yes your problem, is FAR from rare and in fact its very common most guys simply take an old spark plug,
put it in a vise and bust out the old porcilian center and re-thread the interior of the remaining metal hex.
or buy a tool like comps
https://www.summitracing.com/parts/...-_-comp-cams&gclid=CJ3wuuyJ8tACFYOFswodCKYKvw
cca-4792_cp.jpg


pro-66792.jpg

you then buy a 6" threaded bolt, screw it into the plug body
threadbolt.jpg


with similar thread pitch and thread that fully threaded bolt about 3" of that bolt entending past the spark plug base,
and heat and bend it with your propane or acetolene torch in a shallow curve,
now BRAZE or weld a cheap socket head wrench to the bolt head so it can,t move off the bolt and indexed so ,
its pointing strait up when the bent internal part of the piston stop points strait down ward

boxen.jpg

now you can stick the bent bolt into the cylinder, thread the bolt body into the head and once its seated in the head,
you can easily index the bent part to point down into the cylinder where it will contact the piston as it rotates
which a strait bolt would not do due to the shallow enterance angle
be aware that you need to be able to feel the engine stop when it contacts the probe tip, if you don,t manually turn the engine fter first removing the other spark plugs ,
and backing off the rockers the resistannce to rotation the valve train and compression have will make felling the piston contacting the piston stop difficult,
and you damn sure don,t want to bend or break the piston stop.

ignoregrumpy.jpg
 
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Re: resistance to rotation, of crank during short blk assembly
DEAL WITH A QUALITY MACHINE SHOP with a GREAT REPUTATION that depends on maintaining good customer feed back for repeat work.
a competent and experienced machine shop, machinist, you can trust to point out whats REQUIRED and what is SUGGESTED is a very valuable asset , you really should look for and researching what you think needs to be done, how that is accomplished and why its likely necessary in any particular application, goes a long way toward preventing both disagreements and wasted money on an engine build AS does having access too or better yet owning some precision measuring tools that allow you to check and verify that any machine work you pay for was in fact correctly done!

sometimes IM absolutely amazed at the way obvious indication thats somethings very wrong with an engine during the assembly process are being ignored by guys that seem to be clueless to the obvious indications that theres a serious problem.
I get a call from a friend who has a 455 Pontiac, on his engine stand in his garage, its his first engine build, that hes in the process of assembling, and btw this doesn,t just apply to Pontiac engines,he got the block back from the machine shop and has a new crank shaft, he drops the bearings in place coats them with assembly lube, drops the crank into the bearings and installs the main caps , after torquing the main caps, to the listed specs ,he finds it took over 80 ft lbs to get the crank to rotate, in the bearings.
bearings do come in different sizes and crank journals can obviously be cut and polished to different sizes, and its not unusually for a crank to have some or all journals, measure slightly different that the manufacturers intended diam. so measuring and checking each bearing clearance and journal is mandatory,..that resistance to easy rotation, should have been a huge flashing red light signal, with sirens blaring, that something was terribly wrong, a crank with no connecting rods installed should spin freely with minimal finger pressure.
yet his lack of experience and his thinking that the machine shop must have checked all this out before they gave him the components had him thinking that this condition must be normal, he was about to install the connecting rods and pistons but luckily thought to call and ask questions.
the resulting checks showed he had installed a standard crank with .0010 oversize bearings and never used any plasti-gauge or bothered to measure.
FIRST GEN, SBC CLOYES ROLLER TIMING SET
https://www.summitracing.com/parts/clo-9-1100/overview/

MARK IV BBC CLOYES ROLLER TIMING SET 1965-90
https://www.summitracing.com/parts/clo-c-3024x/overview/

MARK VI BBC CLOYES ROLLER TIMING SET 1991-95
https://www.summitracing.com/parts/...-specific/engine-family/chevy-big-block-gen-v


If he had continued he would surely have had a engine come apart withing minutes of starting as the main bearings were totally ruined. as it was he needed to replace the main bearings and polish the crank, checking the block amazingly indicated it was not warped or in need of re machining.... we ALL make mistakes its part of the learning process, but at the first indication something seems to be not correct STOP ASK QUESTIONS
IF your ever unsure STOP and ask questions before you proceed, NEVER assume ,ALWAYS do research before you guess! and it sure helps to have experienced friends so join the local ho rod clubs, yes 70%-90% of the guys will be clueless or unwilling to help, but theres usually at least one experienced old geezer who is willing to teach new guys, if your willing to supply lunch or a few beers during the process
pont3.jpg

pont1.jpg

pont2.jpg

ear.
Picture106r.jpg

on paired connecting rods, bevel side faces out toward crank counter weight, smooth side faces the adjacent rod face
bearingh9.jpg

http://garage.grumpysperformance.co...d-side-clearance-dont-assume.4690/#post-12703
http://garage.grumpysperformance.co...ank-durring-short-blk-assembly.852/#post-1534
http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/page-2#post-75256
12/13
All ’87-and-later Chevy blocks come with a one-piece rear-main seal. This requires the use of a late-model one-piece rear-main seal crank. Starting with the ’88s, most passenger-car engines converted to hydraulic roller cams that required a spider. This is a truck block where the spider mounting bosses are not drilled and tapped, because the truck engine used a flat-tappet cam. These can be easily drilled and tapped to mount the spider for a hydraulic roller cam.
the crank takes far m0re stress and or abuse during a few power shifts,
changing gears at 6000 rpm, than anything you'll,
potentially do to the bearings or crank with a lead shot,filled plastic mallet,
driving that crank, forward and back in its bearings ,on the cranks center line axis.
naturally I assume your not trying to break or bend anything , your simply seating the thrust bearings shell upper and lower halves in the block.
1717268941375.png
yodam.jpg

yodaq.jpg

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/#post-37676
tru3.jpg


tru4.jpg


thr1.jpg

A simple modification to the upper thrust bearing may be beneficial in some engines. Install the upper thrust bearing in the block to determine which thrust face is toward the rear of the engine. Using a small, fine tooth, flat file, increase the amount of chamfer to approximately .040" (1 mm) on the inside diameter edge of the bearing parting line. Carefully file at the centrally located oil groove and stroke the file at an angle toward the rear thrust face only, as shown in the illustration below. It is very important not to contact the bearing surface with the end of the file. The resulting enlarged ID chamfer will allow pressurized engine oil from the pre-existing groove to reach the loaded thrust face. This additional source of oiling will reach the loaded thrust face without passing through the bearing clearance first (direct oiling). Since there may be a load against the rear thrust face, oil flow should be restricted by that load and there should not be a noticeable loss of oil pressure. This modification is not a guaranteed "cure-all". However, the modification should help if all other conditions, such as surface finish, alignment, cleanliness and loading are within required limits.
bearing41.jpg

ThrustBearingModParallel01a.jpg

trustbca.png

thrustb1.jpg

thrustb2.jpg


Last edited: A moment ago



0704ch_17_z+chevy_big_block.jpg

mark iv blocks
mrkiv.jpg

mark v blocks
markv.jpg

(keep in mind that ALL '91 and later Gen.V and Gen.VI big blocks come with 4-bolt main caps. The two-bolt big blocks are no longer in production
MANY BUT NOT ALL aftermarket head designs have been modified to work on both the early MARK IV 1965-90 and later MARK V & VI blocks 1991-later.)

BTW, , on BIG BLOCKS the oil pumps and oil filter adapters are different due to the block oil filter recess and rear seals being different
GEN 4 or MARK IV
bbcmk4.jpg


GEN V and VI
bbcmkv.jpg


markvioilp.png

MARK VI BLOCK OIL CONNECTIONS
RELATED INFO
viewtopic.php?f=44&t=4543&p=12111&hilit=hemi#p12111
http://bangshift.com/general-news/ebay- ... never-run/

0704ch_05_z+chevy_big_block+.jpg

0704ch_08_z+chevy_big_block+.jpg



most big block blocks will take a .060 over bore without issue some will take .100 but your almost sure to have very thin bore walls that won,t seal the rings well, and keep in mind many of those blocks have internal water passage rust issues after all many are 25-30 plus years old

bore x bore x stroke times 8 x .7854= displacement
example
a 4.310 " x 4.310" x 4.25" x 8 x .7854=496 cubic inches

pistonporty1.jpg

http://www.grumpysperformance.com/oct18/ringtech.jpg



http://www.grumpysperformance.com/ringslack.jpg

[IMG]http://www.pochefamily.org/outboard/images/RingsSM2.png[/SIZE]

[COLOR=rgb(64, 0, 64)][SIZE=5][IMG]http://www.grumpysperformance.com/rings-fl.jpg
[/COLOR]
read these links and sub links

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

viewtopic.php?f=69&t=1420

viewtopic.php?f=69&t=5123

viewtopic.php?f=69&t=6125

viewtopic.php?f=69&t=189

BUY A FEW REFERENCE BOOKS ITS MONEY VERY WELL SPENT

bbce1.jpg


bbce2.jpg


bbce3.jpg


bbce4.jpg

Common assembly clearances
there are flat cranks or 180 degree designs
Cr2.jpg

(ALWAYS consult your piston manufacturer for recommended clearances. Many pistons require a tighter bore)

Piston to bore 0.0055 - 0.0065" ( measured at centerline of wrist pin, perpendicular to pin)


Piston ring gap MINIMUM end clearances Top 0.022"
2nd 0.016"
Oil 0.016"

Wrist pin 0.0006 - 0.0008" in piston, 0.0008 - 0.0010" in rod for full floating pin (End play 0.0 - 0.005"

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" , 0.005 - 0.007 crankshaft end play

Piston to head clearance 0.035 MINIMUM including gasket (steel rods), 0.060" MINIMUM aluminum rods

Valve to piston clearance MINIMUM 0.020" exhaust , 0.010" intake NO VALVE FLOAT
Recommended: 0.080 intake, 0.100 Exhaust (steel rods) 0.100 intake, 0.120 Exhaust aluminum rods
related info
viewtopic.php?f=44&t=4125&p=16379&hilit=pontiac+related#p16379

viewtopic.php?f=53&t=5933&p=18274&hilit=cam+degree+tools#p18274

http://garage.grumpysperformance.com/index.php?threads/main-cap-fit-in-block.5945/#post-34251

http://www.chevelles.com/forums/showthread.php?t=379622

http://boxwrench.net/specs/pont_265-455.htm

viewtopic.php?f=53&t=2726

viewtopic.php?f=59&t=1390&p=3423&hilit=precision#p3423

http://vintage.mitchell1.com/PClubData/ ... 745121.pdf

http://www.amazon.com/How-Build-Perform ... 1884089674

http://www.mre-books.com/pontiac/engines.html

http://www.highperformancepontiac.com/t ... index.html

http://www.highperformancepontiac.com/t ... index.html

btw these are not all that bad as an engine stands, he purchased it from northern tool, I can,t see how anyone who is serious about building engine does it without at lease a reasonably strong/ stable engine stand
http://www.northerntool.com/shop/tools/ ... _200442439

790026_lg.jpg

ENGINE BUILDING TOOL Shopping WISH LIST List
ENGINE STAND
foldst.png


Tapered Ring Compressor
pro-66767_w.jpg

THIS BEAM STYLE TORQUE WRENCH IS THE TYPE TORQUE WRENCH YOU WANT TO CHECK ROTATIONAL RESISTANCE
beam_torque_wrench.jpg

BUT NOT WHAT YOULL USE TO TIGHTEN HEAD BOLTS

as to the rotational smoothness
, be aware that, all assembly lubes and oil on blocks bore the rings ride over and all bearing surfaces, coated with oil and assembly lube provide a surface shear tension that must be broken before the crank turns,
so its not un-usually for the rotating assembly after the pistons and rings are installed, too require lets say 35 ft lbs to get the assembly too start too spin ,but only 15-26 ft lbs to keep in rotating , (low tension rings provide less drag) you can generally call the piston ring manufacturers and they should know approximately what torque reading on the crank snout,a socket and a torque wrench will require to have the engine assembly rotate with their rings installed.
a crank snout, turning socket,but if that short block assembly,takes over 35-40 lbs to start it rotating once its assembled without cylinder heads attached, you've got serious issues, like cam lobe to connecting roods hitting or a connecting rod facing the wrong way on the crank journal, or the wrong size bearings, or the crank journals not the right size, badly polished or not round
pro-67491_w.jpg

that's why you'll need a torque beam deflection torque wrench to check that

beam_torque_wrench.jpg


HUSKY $88 (worked rather well, over all I was pleased)
http://www.homedepot.com/p/Husky-1-2-in-Click-Torque-Wrench-H2DTW/202916180?N=5yc1vZc6ev
FOR HEAD BOLTS AND MAIN CAP STUDS ETC.
youll need a good quality torque wrench
torquewrench.png

Piston Ring Squaring Tool

http://www.grumpysperformance.com/
ringsqtool.jpg
[/B]




http://garage.grumpysperformance.com/index.php?threads/damper-honing.4975/#post-13912
damper tool
pro-66514_w.jpg


Degree Wheel
checking lifter
pro-66838_w.jpg

degree wheel

degreesum.jpg


Dial Bore Gauge

Pushrod Length Checker

prctool.png

http://www.summitracing.com/search/...d-length-checkers?autoview=SKU&ibanner=SREPD5
Proform Pushrod Length Checkers 66789 SBC 3/8" rocker studs

Proform Pushrod Length Checkers 66790 SBC 7/16" rocker studs

Proform Pushrod Length Checkers 66806 BBC 7/16" rocker studs

Oil Pump Primer

SBCprimer.jpg



23301a.jpg

http://www.harborfreight.com/36-piece-3 ... 60669.html

harbor freight has cheap and perfectly acceptable calipers
calipersaa.jpg

http://www.harborfreight.com/6-in-dial-caliper-62362.html
18512.jpg

http://www.harborfreight.com/1-inch-travel-machinists-dial-indicator-623.html
16336.jpg

http://www.harborfreight.com/multipositional-magnetic-base-with-fine-adjustment-5645.html
spring micrometers,
pro-67390_w_ml.jpg

a crank snout, turning socket,
pro-67491_w.jpg

a dead blow mallet ,
20443a.jpg

a can of moly spray lube,

DECK BRIDGE
deckbridge.jpg

http://www.summitracing.com/parts/PRO-66797/
ring install pliers
pring3.jpg

piston ring filer,
prf4.jpg

rings3.jpg

GEAR PULLERS
4YT14_AS01.JPG

http://www.hotrod.com/how-to/engine/ccrp-9901-affordable-engine-building-tools/

http://www.powerhouseproducts.com

https://www.proformtools.com/

http://www.bierbros.net/EngineBuildingAndPrecisionTools.html

http://www.superchevy.com/how-to/148-0505-engine-building-tools/

http://www.goodson.com/
 
Last edited by a moderator:
Re: resistance to rotation, of crank durring short blk asse

hy grumpy im building a pontiac 400 , engine has a rope seal , in stalled the crank and rods/pistons and i know the rope seal adds more drag, the amount of pounds needed to get crank moving is 39 lbs and to keep it rotating is 30 lbs. is this normal,,,,, is it ok for a rope seal ????,,, i know its a little on the high side according to your specs...thanks
 
the fact is setting the engine bearing clearances and selecting the type of bearing surface, is a judgement call based on both intended use and the oil viscosity you intend to use.
the higher the average rpm range the greater the oil flow rate over the bearing surfaces and the greater the need for cooling the oil,the difference between what will function fairly well and what would be ideal may not be a great deal different, but in the long term, you should try to get things as close to ideal as you can, every choice made is a compromise in several areas, some choices are of course a bit more critical to the engine function that others and some cam be compensated for to some degree with other parts selected.
example. slightly larger bearing clearances will require a bit larger oil flow rate so a high volume oil pump might not be a bad idea, but that would logically usually require a larger capacity oil pump to provide that flow increase,a baffled oil pan and windage screen to control the oil flow return.
BTW youll find through experience that many of the main bearing sets tend to have the rear main bearing is designed with a slightly larger clearance for some reason

look at the charts below and youll see how the clearance effects oil flow rates ,heat build-up and load capacity, it should become obvious that clearance in the .002-,003 range provide a near ideal compromise in characteristics and a slight change has very little effect , but larger bearing clearances increase flow (with in that .002-.003 range), thus cooling as greater flow absorbs and transfers heat out of the bearing surface slightly more effectively. while tighter clearances slightly increase load capacity but require a thinner viscosity oil being used.

yes I use both micrometers and snap gauges and cross check with plasti-gauge
and yes when you compare the crushed width of the plasti-gauge youll find it rarely falls as an exact match to the bar chart tape that is packaged with it so you can judge clearance based on crush width
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/
plas1v.jpg

plas2v.jpg


Directions for crankshaft grinding and polishing
Crankshaft journal surfaces should be ground and polished to a surface finish of 15 micro inches roughness average Ra or better. Journals on highly loaded crankshafts such as diesel engines or high performance racing engines require a finish of 10 micro inches Ra or better.

The above is a simple straight forward specification which can be measured with special equipment. However, there is more to generating a ground and polished surface than just meeting the roughness specification. To prevent rapid, premature wear of the crankshaft bearings and to aid in the formation of an oil film, journal surfaces must be ground opposite to engine rotation and polished in the direction of rotation. This recommendation and examination of the following illustrations will help make the recommendation more clear.

Metal removal tends to raise burrs. This is true of nearly all metal removal processes. Different processes create different types of burrs. Grinding and polishing produces burrs that are so small that we can't see or feel them but they are there and can damage bearings if the shaft surface is not generated in the proper way. Rather than "burrs", let's call what results from grinding and polishing "microscopic fuzz." This better describes what is left by these processes. This microscopic fuzz has a grain or lay to it like the hair on a dog's back. Figure 1 is an illustration depicting the lay of this fuzz on a journal. (Note: All figures are viewed from nose end of crankshaft.)

crankfigure1.gif

The direction in which a grinding wheel or polishing belt passes over the journal surface will determine the lay of the micro fuzz.

In order to remove this fuzz from the surface, each successive operation should pass over the journal in the opposite direction so that the fuzz will be bent over backward and removed. Polishing in the same direction as grinding would not effectively remove this fuzz because it would merely lay down and then spring up again. Polishing must, therefore, be done opposite to grinding in order to improve the surface.

In order to arrive at how a shaft should be ground and polished, we must first determine the desired end result and then work backwards to establish how to achieve it. Figure 2 depicts a shaft turning in a bearing viewed from the front of a normal clockwise rotating engine. The desired condition is a journal with any fuzz left by the polishing operation oriented so it will lay down as the shaft passes over the bearing (Figure 2).

crankfigure2.gif

The analogy to the shaft passing over the bearing is like petting a dog from head to tail. A shaft polished in the opposite direction produces abrasion to the bearing which would be like petting a dog from tail to head. To generate a surface lay like that shown in Figure 2, the polishing belt must pass over the shaft surface as shown in Figure 3.

crankfigure3.gif

The direction of shaft rotation during polishing is not critical if a motorized belt type polisher is used because the belt runs much faster than the shaft. If a nutcracker-type polisher is used, then proper shaft rotation must be observed (Figure 4). Stock removal during polishing must not exceed .0002" on the diameter.

crankfigure4.gif

Having determined the desired surface lay from polishing, we must next establish the proper direction for grinding to produce a surface lay opposite to that resulting from polishing. Figure 5 shows the grinding wheel and shaft directions of rotation and surface lay for grinding when viewed from the front or nose end of the crankshaft. This orientation will be achieved by chucking the flywheel flange at the left side of the grinder (in the headstock). Achieving the best possible surface finish during grinding will reduce the stock removal necessary during polishing.

crankfigure5.gif

The surface lay generated by grinding would cause abrasion to the bearing surfaces if left unpolished. By polishing in the direction shown in either Figure 3 or 4, the surface lay is reversed by the polishing operation removing fuzz created by grinding and leaving a surface lay which will not abrade the bearing surface.

Nodular cast iron shafts are particularly difficult to grind and polish because of the structure of the iron. Nodular iron gets its name from the nodular form of the graphite in this material. Grinding opens graphite nodules located at the surface of the journal leaving ragged edges which will damage a bearing. Polishing in the proper direction will remove the ragged edges from these open nodules.

All of the above is based on normal clockwise engine rotation when viewed from the front of the engine. For crankshafts which rotate counterclockwise, such as some marine engines, the crankshaft should be chucked at its opposite end during grinding and polishing. This is the same as viewing the crank from the flanged end rather than the nose end in the accompanying figures.

Unlike many engine bearings available today, Clevite engine bearings utilize a superior Clevite TriMetal™ material design. Stamped "Clevite®," this design incorporates the strength of a copper-lead alloy layer on a steel back and finally, a precision electroplated white metal "babbitt" third layer. TriMetal™ is an ideal bearing design producing good to excellent characteristics when judged for conformability, embedability, slipperiness and fatigue resistance.

We constantly monitor the function and operation of our full line of bearings, staying in touch with any changes or developments that new engines may require. And that translates into bearings that are better for your engine. If you're looking for the engine bearings that set the standards, specify Clevite®. Because you won't settle for second best.




bearing1a.jpg

bearing2a.jpg

bearing3a.jpg


as a general rule you select .001 bearing clearance for every inch of bearing journal diameter,
Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" for most engines ( 0.020-0.025 bearing clearance on small blocks, .025-.027 bearing clearance is about ideal, on big blocks ), 0.005 - 0.007 crankshaft end play

http://garage.grumpysperformance.co...ng-clearances-engine-builders-magazine.11965/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/

http://garage.grumpysperformance.com/index.php?threads/building-a-custom-wet-sump-oil-pan.65/

http://garage.grumpysperformance.co...g-up-oil-feed-holes-in-bearings-shells.10750/

http://garage.grumpysperformance.co...m-sure-your-convinced-its-the-oil-pump.11085/

http://garage.grumpysperformance.com/index.php?threads/whats-a-windage-tray-do.64/

Re: resistance to rotation, of crank durring short blk asse
you'll
need accurate precision measuring tools

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/

http://garage.grumpysperformance.com/index.php?threads/main-cap-fit-in-block.5945/#post-34251

OK Im assuming your measuring the crank resistance without any rods attached here. correct?
if the rope rear seal was liberally coated with moly assembly lube the crank alone should require a good deal LESS torque to allow it to spin , like 15-20 lbs max, so,Id first try whacking the cranks rear flange in all directions with a large rubber mallet several times at about every 45 degrees around the clock, going around at least 5 full times to fully seat the seal on the rear main journal. as that won,t require any dis-assembly.
if after removing the rear main cap you find its only the rear main rope seal causing the extra drag id suggest trimming it and reinstalling it and try for a 20 lb drag, if its a bit higher it will work, but that's not ideal, still it will wear in, during engine operation so its not going to stop the assembly provided thats determined to be the source of your resistance to rotation.
if it drops to 15-20 lbs you good to continue, with further assembly, if not,STOP! pull the rear main cap and lower seal on the block and check the resistance to rotation, it should drop to that 15 lbs, if not you have other issues, if after removing the rear main cap you find its only the rear main rope seal causing the extra drag id suggest trimming it and reinstalling it and try for a 20 lb drag, if its a bit higher it will work, but that's not ideal, still it will wear in, during engine operation so its not going to stop the assembly provided thats determined to be the source of your resistance to rotation., did you use plasti-gauge on the bearings to verify clearances? did you coat all the bearings with assembly lube during final assembly?
are you sure all the main caps are on the correct journals with the caps facing the correct direction and are all the bearings seated correctly?
have you checked to see if the journal edges and bevel on the bearings are touching, or binding?
you might simply need to trim the rope seal a bit and reinstall it , but I sure would figure out why your having that much resistance before continuing the build, if thats the crank alone in the block that takes 30 plus ft lbs to keep spinning. with the rear main lower cap removed you better start checking to locate the reason ,
now if you remove that lower rear main cap and don,t see a noticeable drop in resistance Id sure look at the thrust bearing clearance and other bearing clearances ? ? ?
the difference between assembling an engine correctly and just bolting parts together is recognizing that each step in the process will result in clues to its correct or faulty assembly, and having the smarts to ask questions and stop and correct anything that you find that might be a problem or indication that some parts not fitted correctly and as you gain experience youll find ignoring obvious signs of potential problems almost always comes back to bite you in the ass later.
and yes I learned that the same way 99% of us did, by screwing up my first few engine builds in some ways, now that doesn,t mean those engines didn,t run, but it sure means that they didn,t run to nearly their full potential or last as long as I expected or in some other way taught me that stopping and asking questions before proceeding was far preferable too the results youll get assuming that
the USE A BIGGER HAMMER!
AND
plunge FORWARD REGARDLESS!
APPROACH DOES WORK!

BECAUSE with experience youll find they RARELY DO!



http://www.wallaceracing.com/torque-engine-specs.html
eddg1.jpg

VERIFY THE EDGE OF THE MAIN CAP BEARINGS IS NOT BINDING ON THE JOURNAL SIDE BEVEL RADIAS (BLUE /GREEN AREAS)
eddg2.jpg

eddg3.jpg

VERIFY THE MAIN CAPS FACE THE CORRECT DIRECTION AND ARE IN THE CORRECT LOCATION, SEATED CORRECTLY AND TORQUED IN STAGES TO CORRECT TORQUE, BEARING TABS IN CORRECT PLACE


eddg4.png

eddg5.png

eddg6.png

eddg7.png



rope rear main seals can be used and they work reasonably well, but there are vitron seals available that tend to last longer and seal better

obviously you first need access to the rear main seal, and its a whole lot easier if the engines out of the car, on an engine stand , during the instal process, but in any case youll remove the old rear main seal, carefully clean and degrease the area in the block and main cap where the seal you selected to use is installed.
if your using the vitron/rubber style rear main seal , the process duplicated the chevy rear seal info posted earlier,the surface facing the block or cap is lightly coated with a good flexible sealant, the seal installed with the flexible lip facing the front of the block, the ends of each seal get a dab of silicone sealant and a bit of MOLY grease on the inner surface the crank journal rests against, once the caps installed, hot oil from the running engine expands the rope seal, in theory sealing the rear main, in most cases it does a decent job.

if your using a rope/graphite seal the groove in the block and main caps carefully cleaned and degreased with brake cleaner and a brush. IF access is available ,the rope seals placed in the groove,with a bead of silicone on the outer edge facing the bottom of the groove in both the block and rear main cap , and its forced into the groove by rolling a large socket over its inner surface, compressing it into the groove,and a razors used on the ends to cut them flush then a dab of silicone applied to each end of the seal where they mate, the seal expands when soaked with hot oil from the running engine, the moly grease tends to prevent wear until the rope seal absorbs oil, in theory applying a low pressure contact seal, that prevents oil leaks.....the vitron seals tend to work a bit better.

the pictures below show a filthy block that needs to be cleaned and the guy trying to install obviously the larger and longer rear main seal from the larger crank diameter that must be cut and modified to fit but the process is nearly identical
rps1.jpg

rps2.jpg

Kit says to use a smooth cylindrical object to pack seal in groove. big deep-socket worked fine.
rps3.jpg


rps4.jpg

rps5.jpg

the rope seal below looks correctly seated but it must be coated with a mix of oil and moly assembly lube before the cranks installed
oilpan04.jpg


oilpan03.jpg

oilpan02.jpg

oilpan01.jpg

Ive occasionally been asked what you can do too reduce the slack in the timing chain if your blocks been line honed,
to straiten the main bearings and that resulted in a slightly closer crank to cam center-line distance,
that results in a slightly increased slack in the stock timing chain sets.
a negligible amount of metal is generally removed from the main bearing saddles in the block, they usually try very hard to minimize that, metal removal so standard parts still fit,during a line hone , but they do sell slightly tighter timing chain sets to correct excess slack if that's required.

SBCprintCustom8.jpg


cloyesunder.jpg


https://www.summitracing.com/parts/clo-9-3100-5
Timing Chain and Gear Set, Original True Roller, Double Roller, -0.005 in., Iron/Steel Sprockets, Chevy, Small Block, Set
for line honed blocks where the crank is .005 closer to the cam


https://www.summitracing.com/parts/clo-9-3100-10
for line honed blocks where the crank is .010 closer to the cam
Timing Chain and Gear Set, Original True Roller, Double Roller, -0.010 in., Iron/Steel Sprockets, Chevy, Small Block, Set

http://www.ehow.co.uk/how_8000662_insta ... ntiac.html

http://www.jbp-pontiac.com/products/gas ... seals.html

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-55314

http://www.tinindianperformance.com/Pon ... 0Seals.htm

http://www.allpontiac.com/rearmain_seal.html

http://www.bopengineering.com/viton_compare.shtml

http://www.bopengineering.com/seal_instructions.pdf

Which Pontiac rear main seal do I need?
At Tin Indian Performance, we sell / advertise our seals according to the main journal size of the appropriate engine that uses them.



Pontiac engines / blocks that have 3 inch mains are 326 / 350 / 389 / 400. Keep in mind that when I say this, it means the cid of the original block casting. Pontiac engines / blocks that have 3.25 inch mains are the 428 and 455 blocks. The most common main journal size for aftermarket blocks is 3"; however, 3.25" mains are also available as well. Now for those who are into measuring things and have the crankshaft available to them, the 3 inch main blocks have a crank sealing surface of approximately 3.188 inches. This would require the TIP-RM300 seal The 3.25 inch main bearing cranks have a sealing surface of 3.436 which would use the TIP-RM325.

So when ordering your seal, know what main bearing journal size you have.
If it is a 3" main you will need a TIP-RM300.
If it's a 3.25" rear main journal, then it is a TIP-RM325.

example of (engine building" vs parts assembly)
yodam.jpg

yodaq.jpg

Id bet 80% or more of the people assembling parts have never checked most component clearances ,
except in most cases for ring end gap and bearing to crank journal, as thats almost mandatory.
things like,
piston to the cylinder head (quench)
piston to valve,
rocker slot to rocker stud,
connecting rod to cam lobe,
connecting rod to block skirt,
piston skirt to crank counterweight,
cam button to the timing cover,
spring bind height,
rod side clearance,
thrust bearing clearance,
ring end gap and piston slot back clearance on rings.
piston to bore clearance.
pushrod to the cylinder head, or guide plate,
crank journal taper and concentricity and surface smoothness
cylinder head surface and not being warped
cleaning out all the threaded holes with a tap.
sonic testing bore walls
having the block , crank and heads checked for micro-cracks
verifying the oil pump drive shaft has about .050 clearance with the distributor fully seated,
replace and shim distributor gear with new cam installation
verify oil pump relief spring function, test to ensure it opens at no higher than 70 psi
checking for crank straitness.
verify crank journal to counter weight junction has consistent radias
verify head gasket opening is at least .030 larger than bore diameter all the way around bore circumference
verifying main cap concentricity and shoulder depth.
verify pushrod length and valve train geometry.
timing chain slack, and/or lack of clearance to the timing cover.
verify theres no crud inside push rods or block oil passages.

verify the block oil passages and bearing oil holes align properly (correct and bevel as required)
bearingoffset2.jpg

p117190_image_large.jpg

MEASURE CAREFULLY

bearingjournalz.jpg

journaltapers.jpg




chamferedhole.jpg


1310.jpg

crnk1a.jpg

BaseCircleDiaaaa.jpg

notice how the rod bolts come close to the cam bearings as the pistons reach top dead canter in the bores
block-clearance.jpg

rodcaptoblockclearance.JPG


crnk6.jpg



reading links and sub-links will take days ,
but it's sure to save you hundreds of dollars ,
and weeks of wasted effort.


http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/another-rings-end-gap-question.14994/

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.co...alves-and-polishing-combustion-chambers.2630/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

http://garage.grumpysperformance.com/index.php?threads/cam-bearing-install-tools-install-info.1479/

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.com/index.php?threads/cylinder-head-resurfacing.15767/

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/

http://garage.grumpysperformance.com/index.php?threads/engine-assembly-tips.4294/
 
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Re: resistance to rotation, of crank during short block assembly
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

http://garage.grumpysperformance.com/index.php?threads/rotating-assembly-bearings.9527/#post-35037
Try repacking the Rear Main Rope Seal tighter Elsalvidor .
They do have considerable drag compared to a rubber seal. Till the engine fires & spins 50-100 Revolutions around.
Rope Seal burnishes in.
No perfect rear main seal made for a Pontiac except for Original NOS GM ASBESTOS Fiber Rope Seal.
Best made ever. Almost unobtainable.
EPA to blame why gone forever.

Rubber Viton works best in Indian Adventure Aftermarket $5-6k Race block & with Billet Crower crankshaft.

You can always remove Crankshaft, remove upper seal half. Lower cap seal.
Install crank.Torque main caps down to specs.
Recheck. Will be 5-10 Ft/lbs. If clearances correct.
Pontiac Factory cranks are super tangle line straight. Crankpin index near perfect. Unless crankshaft grinder goofed up.

The original GM Asbestos Fiber Rope Rear Main seal NOS in box worth up to $400 - $500 to Pontiac Die Hards like me.
They worked that good.
Makes a Viton look Meak....They will drip some oil no matter whats tried.

Original GM Will Not.


egcl1.png

egcl2.png




the first few rule's of GRUMPY'S engine assembly

(1) THINK THINGS THROUGH CAREFULLY ,
WRITE DOWN A LIST OF COMPONENTS ,

MAKE DARN SURE THE LIST IS COMPATIBLE WITH,
and AT LEAST SEMI-REASONABLY PRICED WITHIN YOUR BUDGET.
FOR WHAT YOU INTEND TO BUILD AND RESEARCH THE RELATED MACHINE WORK,

RESEARCH CAREFULLY THE COMPONENT INSTALLATION AND INTENDED USE ,
AND POWER BAND THE PARTS WILL REQUIRE

AND FIND AN EXPERIENCED MENTOR.

(2) if in doubt, about how to do anything, on an engine, do some detailed research,
find and compare at least 3-5 valid trust worthy sources info,
read the instructions over again, several time's very carefully
and if available watch several related videos.

(3) if any component will not easily function as designed or requires a good bit of physical force to install ,
or your not 100% sure your doing something CORRECTLY

STOP, FIND OUT EXACTLY HOW THE PARTS SUPPOSED TO FIT AND FUNCTION,& WHY! YOUR HAVING PROBLEMS
theres a reason, and you better verify your clearances are correct , and your following the instructions before you proceed.

(4) never assume the parts you purchased can be used without carefully , cleaning them prior too,
checking the physical condition, verifying clearances and using the correct sealant, lubricants etc.



(5) the quality of a component is generally at least loosely related to the cost to produce it,
and the amount of detailed research and quality machine work that went into its production.
if you got a significant reduced price, theres typically a reason.
it might simply be because a new improved part superseded the one you purchased,
but it might be a far lower quality imported clone with lower quality materials and machine work.
its the purchasers responsibility to research quality.

(6) if you did not do the work personally or at least take the effort to verify it was done correctly and personally verify clearances

ITS almost a sure thing that it was NOT done , correctly, and yes that mandates you fully understand what your looking at,
and how the components are supposed to function and have high quality precision measuring tools.

(7) ITS ALMOST ALWAYS FASTER AND LESS EXPENSIVE , AND PRODUCES BETTER RESULTS IF YOU,
BUY FEWER HIGH QUALITY PARTS & DO THINGS CORRECTLY THE FIRST TIME
 
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Re: resistance to rotation, of crank durring short blk asse

thanks guys . the crank and pistons and rods are installed ,, and it takes 39 lbs to get it started and it drops to 30 lbs to keep it rotating,,, im assuming this is ok ?? its a little on the high side ,,,, i also measured it with just the crank and it took 19 lbs to get it moving and 10 lbs to keep it rotating .....thanks again
 
Re: resistance to rotation, of crank durring short blk asse

elisalvador said:
thanks guys . the crank and pistons and rods are installed ,, and it takes 39 lbs to get it started and it drops to 30 lbs to keep it rotating,,, im assuming this is ok ?? its a little on the high side ,,,, i also measured it with just the crank and it took 19 lbs to get it moving and 10 lbs to keep it rotating .....thanks again
a good wack with a mallet ,
thr1.jpg


will move it into alignment,
but it should be sleeved or pinned , once perfectly aligned,
too assure repeated,
perfect alignment during re-assembly

IMG_0465.jpg


IMG_3659.jpg


Have a block with SPLAYED main cap outer bolts will significantly reduce main cap movement

Eagle-CAPS3.jpg


IMG_3662.jpg

IMG_3661.jpg

HOLLOW DOWELS that fit into machined recesses,machined around the inner main cap bolts in slight enlarged main bolt cap and block bolt holes with a slight interference fit that extend about 1/4 into each bolt hole, from the main cap /block parting line, tend to significantly reduce main cap movement
Mains005.jpg

0108gmhtp_motown04_zoom.jpg


yodam.jpg

yodaq.jpg

A simple modification to the upper thrust bearing may be beneficial in some engines. Install the upper thrust bearing in the block to determine which thrust face is toward the rear of the engine. Using a small, fine tooth, flat file, increase the amount of chamfer to approximately .040" (1 mm) on the inside diameter edge of the bearing parting line. Carefully file at the centrally located oil groove and stroke the file at an angle toward the rear thrust face only, as shown in the illustration below. It is very important not to contact the bearing surface with the end of the file. The resulting enlarged ID chamfer will allow pressurized engine oil from the pre-existing groove to reach the loaded thrust face. This additional source of oiling will reach the loaded thrust face without passing through the bearing clearance first (direct oiling). Since there may be a load against the rear thrust face, oil flow should be restricted by that load and there should not be a noticeable loss of oil pressure. This modification is not a guaranteed "cure-all". However, the modification should help if all other conditions, such as surface finish, alignment, cleanliness and loading are within required limits.
bearing41.jpg

ThrustBearingModParallel01a.jpg

trustbca.png

bearing41.jpg

ALLOWING MAIN CAPS TO MOVE< UNDER HIGH LOAD STRESS WILL EVENTUALLY RESULTS IN CRACKED BLOCKS OR MAIN CAPS
http://garage.grumpysperformance.com/index.php?threads/splayed-main-caps.1014/#post-12226

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-face-wear.15017/#post-84959

http://garage.grumpysperformance.co...gine-block-main-cap-movement.6162/#post-19172

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/
heres some info from napa
http://knowhow.napaonline.com/know-notes-measure-engine-bearing-clearance/
bearing_clearance_feature.jpg

KNOW-HOW NOTES: HOW TO MEASURE ENGINE BEARING CLEARANCE


When rebuilding an engine, there is nothing more critical than getting the bearing clearance correct. Every engine has its own bearing clearance specs, but the measuring procedure does not change. There are two main methods used for checking bearing clearance – Plastigage® or gauges.

Plastigage®
Plastigage® has its place, as it serves a purpose for backing up and verifying your bearing clearances. Plastigage® is a special plastic that expands a specific amount when squeezed. Sold in sleeves of threads for specific thickness ranges, Plastigage® works really well in situations where the components are not being completely removed, such as in-engine bearing replacement, and other non-automotive uses. Originally put on sale in 1948, Plastigage® is fairly accurate and the method of choice for many DIY enthusiasts.

IMG_7335a.jpg

Plastigage® is quite useful, so don’t automatically throw it out. It is a good way of verifying your measurements.

In reality, the right way to check bearing clearances is with the proper tools. In order to check the clearances for rod and main bearings, you need a set of micrometers and a dial-bore gauge. These are readily available at budget prices, but if you are going to use them a lot, better quality tools are advised.

Micrometer
This looks like a horseshoe with a round handle attached to one leg. Micrometers typically only adjust 1”, so you need multiple sizes to get the job done. A 1-6” set usually has the sizes you need for most jobs.

IMG_6558a.jpg

This a complete micrometer set that will cover just about anything you could need for automotive work.

Dial-Bore Gauge
This tool uses a dial indicator on a post with a small wheeled measuring apparatus. These are adjustable through graduated post extenders that increase the diameter of the measurement circle.

IMG_6564a.jpg

The dial bore gauge measures the inside of round holes, such as the bearing journals.



IMG_6565a.jpg

This one tool can measure 2″ up to 6″ diameter holes.
https://www.enginelabs.com/engine-tech/blueprint-series-measuring-and-setting-bearing-clearances/

https://www.zoro.com/fowler-dial-bore-gage-set-526463000/i/G0059624/?recommended=true






Both tools are needed in order to check the interior and exterior dimensions of the crankshaft, rods and engine block journals, as well as the thickness of the bearings themselves. Making all of this happen can be tricky, so here are a few tips to help you work through the process.

Using a micrometer means following a couple of rules. The key to a micrometer is not to tighten it too much. There are two knobs – a large knob and then a smaller one. The smaller knob clicks when the micrometer is in contract with the part. DO NOT use the larger knob to tighten the mic onto the part as this can damage the tool.

Reading a micrometer can be confusing, they are graduated differently than rulers. The inside barrel is marked in .100” (large) and .025” (small) notations. Once you reach those marks, the scale on the thimble (large rotating knob) comes into play to get the finite measurements. The thimble is scaled in .001 divisions from .000 up to .025”.

IMG_6562a.jpg

The hash marks are how you read micrometers. It takes some practice, and unless you use them daily, you will forget over time. Just be patient.

Outer Diameter Measurements
These are fairly simple, just choose the micrometer that covers the range needed and measure. It is a good idea to check the part in three different locations, staying away from the oiling holes as they can throw off the measurements due to the chamfers.

Measuring Bearings
Even though bearings are flat enough, they cannot be accurately measured with calipers, instead you need a micrometer. There are special micrometers available for measuring round inside surfaces, but you don’t have to have one of those. Instead, you can use the shaft of a drill bit (good quality, and use the smooth part, not the fluted section). Place the drill bit on the inside curve, and then measure the bearing. Subtract the thickness of the drill bit (measure, don’t assume), and you will have the thickness of the bearing.

IMG_6571a.jpg

An tube mic is useful for measuring bearings and over inside-curved pieces. In a pinch, you can use a drill bit or pushrod and an outside mic.



IMG_6576a.jpg

This is how bearings are measured. DO NOT use calipers, you can easily scratch the babbit material and ruin the bearing, plus they are just not accurate enough.

Using A Dial-Bore Gauge
Setting up a dial-bore gauge requires using a micrometer. You need the base measurement of the bore, rough is enough. Set the gauge to just over the diameter, using the correct extensions. Set the micrometer to the bore size you need, then place the gauge between inside the mic and rock the gauge back and forth, and side to side. Note the minimum reading, and zero the gauge to that reading.

crop-1a.jpg

Setting the dial bore gauge uses both the bore gauge and a micrometer. Make sure the measuring ends are square inside the micrometer’s anvils (not as shown)

Inside Diameter Measurements
With the dial-bore gauge set to the correct size, place the gauge inside the journal or rod end and rock the gauge back and forth and side to side, just like the setup process. Note the smallest diameter, that is the size of the journal. Just like the outside measurements, take the reading in three different places. One note – the bore must be as it would be in use, so torque the caps to their correct specs and they need to be clean, no oil at all.

IMG_5607a.jpg

Place the gauge inside the journal and move it slowly till you find the largest measurement. Take readings in three places.
that sounds reasonable for a newly assembled Pontiac short block

if you don,t think selecting high quality components and correctly assembling them is important, heres a visual reminder of the results of component failure under high stress.
brokeford.jpg

 
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Re: resistance to rotation, of crank durring short blk asse




as to the rotational smoothness, be aware that, all assembly lubes and oil on blocks bore the rings ride over and all bearing surfaces, coated with oil and assembly lube provide a surface shear tension that must be broken before the crank turns,
so its not un-usually for the rotating assembly after the pistons and rings are installed, too require lets say 35 ft lbs to get the assembly too start too spin ,but only 15-26 ft lbs to keep in rotating , (low tension rings provide less drag) you can generally call the piston ring manufacturers and they should know approximately what torque reading on the crank snout,a socket and a torque wrench will require to have the engine assembly rotate with their rings installed.
a crank snout, turning socket,but if that short block assembly,takes over 35-40 lbs to start it rotating once its assembled without cylinder heads attached, you've got serious issues, like cam lobe to connecting roods hitting or a connecting rod facing the wrong way on the crank journal, or the wrong size bearings, or the crank journals not the right size, badly polished or not round
pro-67491_w.jpg

that's why you'll need a torque beam deflection torque wrench to check that

beam_torque_wrench.jpg


shriner said:
Doing a cam swap and took a pic inside the cam bearing hole and saw this pictured below, is this normal?
conwe.png

HERES THE PICTURE HE POSTED WITH A COMMENT, ADDED!
wearftw.png



any time you find some sign of wear on an engine,part, or indications of parts contacting each other ,where you think they might be a problem,
STOP! look it over and ask questions, before you proceed.
Look closely at the first picture,look thru the cam bearings at the second, third block web ares also, it looks like several counter weights are contacting the block as they rotate, IF it was my engine Id check the trust bearing clearance, and if I found significant wear, replace the cam bearings and the mains and rod bearings, IF YOU find significant wear on the THRUST bearing clearance check, simply because that bearing material went some place and the cam bearing look like they are well worn.
assuming you build the engine correctly and keep the rpm levels fairly reasonable,
the strength of the better quality components tends to GREATLY reduce your chances of expensive crap like this occurring,
simply because the better, name brand forged parts tend to bend a bit rather that come apart as shrapnel, and don,t stretch nearly as easily or develop stress cracks nearly as often as the reconditioned stock components, then I have to ask if the $240-$600 you might have saved , building your aveage performance 350-383 SBC while using cheaper rods and pistons vs refurbish stock parts looks like a real BARGAIN any longer

pistonde1.jpg

pistonde.jpg

you can,t just swap in a different set of pistons or connecting rods,yes you might occasionally find a lower cost set of used rods and pistons at a bargain price,
the pistons must be the correct bore size and the rods and pistons must be balanced to the crank counter weights,connecting rods can be converted to full float pin design but the cost is usually not worth it as better & strong rods can be had at a reasonable price.. and most pistons designed for pressed in pins are rarely top quality and most are not forged
to balance the rotating assembly , plus theres side clearance , bearing size, quench distance and a dozen other potential issues

READ THESE THREAD's
and don,t skip the sub linked info
http://garage.grumpysperformance.com/index.php?threads/engine-balancing.3900/

http://garage.grumpysperformance.com/index.php?threads/engine-balancing.3900/#post-57940


http://garage.grumpysperformance.co...gine-project-dart-shp.3814/page-23#post-21571

http://garage.grumpysperformance.co...t-don-t-destroy-your-budget.10958/#post-48174

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.co...ng-rods-from-pressed-to-full-float-pins.6909/

http://garage.grumpysperformance.co...ng-piston-pin-height-compression-height.5064/

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/balance-damper-question.10462/

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/

http://garage.grumpysperformance.com/index.php?threads/piston-to-bore-clearance.4630/

http://garage.grumpysperformance.co...guess-on-clearances-and-journal-surface.9955/

http://garage.grumpysperformance.com/index.php?threads/obtaining-desired-clearances.4324/

http://garage.grumpysperformance.com/index.php?threads/engine-block-cylinder-wall-thickness.976/
 
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Re: resistance to rotation, of crank durring short blk asse

Will require a new crankshaft likely.
Thrust surface will measure .030"-.060" wear.
 
Re: resistance to rotation, of crank durring short blk asse

and YES, as pointed out by BRIAN, you might find the crankshaft thrust bearing surface so worn, it needs to be welded and re-machined or a new replacement crank installed>
 
Re: resistance to rotation, of crank durring short blk asse

The Scat 9000 Series crankshaft is what I used in my 1994 GMC Suburban.
Special Alloy Iron Crank. 1-piece rear main seal.
$199.99 from Summit. Free shipping.
All New.
Micro polushed & chamfered oil feed holes.
Micrometer checked + - .0002" from GM Blueprint specs.
Not Crower or BRC Billet quality tolerance but still excellent for $200.00.
UDA made.
9000 CRANK Prebalanced to GM SPECS. + - 40 grams is Factory Tolerance.
Scat balances to + - 1 gram middle of Road STOCK GM BOB WIEGHT.
I installed as is . No machine shop balance.
15,000 miles later no ussues.
80 pdi cold oul pressure.
65-70 psi hot.
Idle 45 psi hot.
Vandervell half grooved main bearing set.
Vandervell rod bearings.
Melling M55A 1967-70 Z28 oil pump.
Ran Suburban hard today driving throygh 2-3 foot snow drifts.
 
Re: resistance to rotation, of crank durring short blk asse

Its a pretty good day after all Grumpy.
The Fed Ex guy dropped a small package.
I purchased a NOS FELPRO Pontiac Rear Main Seal.
The original Felpro Logo from 1970's shown on Fleabay.
Just $10 bucks.
Package shows application 1959-70 Pontiavc 389 &400.
Poncho 400 was made till 1979.
So this Rope Rear Main seal was made in late 1969-70 year.
43 years old. Still nice. No Rot.
Its 100% Asbestos center core like Pontiac used original 1955-79.
Take photos later & post.
 
a few links worth reading through

https://www.hotrod.com/articles/ccr...4A7FD6D264A06586D7EAE5DBD81E9DE528EBF92CFA4D9






https://www.hotrod.com/articles/14-engine-assembly-dos-and-donts/

https://www.hotrod.com/articles/engine-assembly-part-2-16-more-dos-and-donts/

https://www.chevydiy.com/pre-assembly-guide-build-chevy-small-block-engines/

https://www.enginelabs.com/engine-tech/engine/buyers-guide-to-ford-modular-4-6-liter-short-blocks/

https://www.chevydiy.com/final-assembly-guide-how-to-build-chevy-block-engines/

https://itstillruns.com/build-350-chevy-small-block-6366860.html

btw, if you buy an engine you did not assemble and you have the oil pan off,
before you re-install the oil pan, on any reasonably newly rebuilt engine,
get out your torque wrench and verify the rod bolt torque is consistent,
its not all that rare for someone to forget to go back over the rod bolts torqueing them to a consistent value,
or for a bolt to loosen a bit if it was not properly torqued,
this may prevent future issues you could easily prevent in doing so.
just start tightening a couple and see if they are consistently torqued.
don,t get crazy just verify
many guys prefer to use a torque beam deflection torque wrench to check that.
you may want to look up the correct torque value for the rods used if you know.
but its likely close to 55 ft lbs, as you check, they should all be consistently torqued to a similar value












beam_torque_wrench.jpg

ctrp_0901_19_z+limited_late_model+race_engine_build.jpg
 
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