how to install a 2piece rear seal crank in 1 piece block

grumpyvette

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http://store.summitracing.com/partdetai ... toview=sku

Moroso part # 38415 $151.95 SBC

http://www.summitracing.com/parts/aaf-a ... /overview/

http://www.summitracing.com/parts/aaf-a ... dia/images

https://www.summitracing.com/search...cending&tw=Rear ma&sw=Rear Main Seal Adapters

http://static.summitracing.com/global/i ... daptor.pdf

posting.php?mode=edit&f=53&t=1042&p=1969

mor-38415_w.jpg


http://store.summitracing.com/partdetai ... toview=sku
Stef's Fabrication 7035 $99 BBC
stf-7035_w.jpg
 
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I got ask, (whats the difference between the one and two, piece rear seal cranks)
1986crankshaftchange.jpg

viewtopic.php?f=71&t=584&p=757&hilit=lakewood#p757
onesealvstwo.jpg

rear_flange.gif


older TWO PIECE REAR SEAL CRANK
one_piece_seal_crank.gif

NEWER ONE PIECE REAR CRANK SEAL DESIGN

http://www.mortec.com/journal.htm

smallv8.jpg


(look at the lower chart)

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"

Be sure the lip seal is positioned leaning inward towards the front of the engine, and the rear seals off-set from the main cap parting line by about 1/4" to reduce the tendency to leak oil
22.JPG

MORE USEFUL INFO
oil%20pump%20stud.jpg

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
Pump-Stud%20Clearance.JPG

failure to use the correct stud, bolt or nut or check clearances when mounting an oil pump can cause problems
pumpss1.jpg

pumpss2.jpg

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
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
bbcmk4.jpg

bbcmkv.jpg

rollerspider.jpg


roller blocks have taller lifter bores, because roller lifters are taller, and a provision to bolt the lifter retainer spring, but they can be very easily used for the earlier flat tappet lifters if desired by simply removing the spider(SPRING RETAINER), keep in mind most roller blocks use one piece rear seals

the flywheel must match the crank hub design, a first gen 283-327- 350 will have a two piece rear seal crank up to about 1987, or so, they look completely different so you should have zero problem telling what your dealing with, and most of those engine are usually internally balanced, the later1987 and up engine is usually a one piece rear seal design that most likely will not work with the older style hub crank and flywheel parts and your bell housing may or may not fit the larger 168 tooth flywheel design , and may require the smaller 153 tooth design, some of the newer sbc engines take a different damper like the LT1 , one piece rear seal crank designs and the BIG BLOCK engines can be EXTERNALLY or INTERNALLY balanced, most of the engines larger than 427 cubic inches were EXTERNALLY BALANCED
read these
viewtopic.php?f=38&t=3900&p=13058&hilit=balancing#p13058

viewtopic.php?f=71&t=447

rear_flange.gif

older TWO PIECE REAR SEAL CRANK
sealrearsur.jpg

don't forget the rear surface of the rear seal to block and main cap needs to be sealed, oil tight
80057.jpg

80063.jpg

one_piece_seal_crank.gif

NEWER ONE PIECE REAR CRANK SEAL DESIGN
keep in mind a SFI SCATTER SHIELD to protect your feet is almost mandatory, on a high performance engine combo
a stock bell housing provides almost zero protection if a flywheel or clutch comes apart at high rpms, and getting your feet cut off in the process is not unheard of as a result

stockbell.jpg

10-03.jpg


cheap iron
http://www.summitracing.com/parts/ZZZ-50-6516/

if you like having FEET!
http://www.summitracing.com/parts/RAM-1511/
 
more engine bearing related info, thats well worth reading thru

http://www.babcox.com/editorial/ar/ar20128.htm

http://www.babcox.com/editorial/cm/cm99828.htm

http://www.hadmac.com/technical_info.htm

http://www.thirskauto.net/BearingPics.html

http://www.babcox.com/editorial/us/us90126.htm

http://www.bobistheoilguy.com/bearingwe ... alysis.htm

http://www.babcox.com/editorial/ar/eb010650.htm

http://www.kingbearings.com/advantages.html

http://www.nb-cofrisa.com/docs/web_fallos_ing.PDF

Engine Balance: Internal vs. External
An engine must be balanced to ensure smooth operation. It minimizes vibration and maximizes engine life. Balancing can be internal, external, or a combination of both.

Balancing an engine means offsetting the weight of the pistons and rods. This involves adding or removing weight from the crankshaft. The Harmonic Balancer and/or the flexplate or flywheel can also be weighted.

Internal Balance
An internally balanced engine has all the counterweight on the crank. External parts like the balancer and flexplate/flywheel have a neutral balance. They will not affect the other rotating parts.

External Balance
If the crank's counterweights are too light, the engine must be externally balanced. This involves adding weight to the harmonic balancer and/or the flexplate or flywheel.

How does it affect performance?
Generally speaking, internal balance is the better option. External counterweights can cause the crankshaft to flex at high rpm. This can cause engine damage. However, either type of balance is fine for most engines.

Converting from external to internal balance can be expensive. It requires a new crankshaft, harmonic balancer, and/or flywheel or flexplate. You may also need to clearance the block for the larger counterweights. Unless you're racing, it's easiest to balance the engine the same way the factory did.

Engine Type Factory Balance Method
Chevy 305/350 (2-piece rear main seal) Internal
Chevy 396-427 Big Blocks
Chevy LS Engines
Ford Modular Engines
Chevy 400/454 External
Ford 302/351W
Chevy 350 (1-piece rear main seal, including LT1) Combination of Internal & External


Notes
Balanced Rotating Assemblies come pre-balanced from the manufacturer. These can be installed without taking the parts to the machine shop.

If you buy an Unbalanced Rotating Kit, you will need to have it balanced before it's installed. The same is true if you buy a crankshaft, connecting rods, and pistons separately.

Crankshafts are listed as internal or external balance. This doesn't mean it's already balanced. It just tells you how it's intended to be balanced. It must be checked with the specific piston and rod combination you use.
 
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SOLVING THE BOLT PATTERN PUZZLE
GM engineers redesigned the crankshafts used in production small-block V8 and V6/90-degree engines in 1986 to use a leak-resistant one-piece rear seal. This change from a two-piece to a one-piece seal required a change in the bolt pattern on the crankshaft flywheel flange. The bolt circle on pre-1986 production crankshafts is 3.58" in diameter. 1986 and later cranks have a 3.00" bolt circle. In addition, all cranks which use a one-piece seal require a counterweighted flywheel for proper engine balance.
Many of the flywheels listed in Group 0.666 are designed for heavy-duty and pre-1986 production crankshafts with a 3.58" diameter flywheel bolt pattern. This larger bolt pattern is recommended for competition engines. If your engine has a crankshaft with a one-piece rear seal, you must use a flywheel (of flexplate) with a 3.00" bolt pattern. Flywheels and flexplates for these cranks are available in 12-3/4" and 14" diameters.

The manual transmission flywheels and automatic transmission flexplates shown in the accompanying charts can be used with Chevrolet small-block V8 and 90-degree V6 engines. When selecting a flywheel or flexplate, be sure to match the outside diameter, flywheel flange bolt pattern, and clutch/converter diameter to your application.
GM Performance Parts offers lightweight nodular iron flywheels for pre-1985 and 1986-up engines. These lightweight flywheels reduce an engine's rotating inertia and improve throttle response. They were originally installed on many high-performance Chevrolets.
All 400ci small-block Chevrolet V8's are extremely balanced, and must use a counterweighted flywheel (or flexplate) for proper engine balance.

crankchart2.jpg
 
http://www.circletrack.com/enginetech/c ... ewall.html

http://cvproducts.com/Uploads/2009Catalogonline.pdf
No major machining operations need to be performed on the block to get the adapter to fit. In addition to the adapter plate-available from GM (PN 10051118), Canton (PN 21-850), and many other manufacturers-a small fixture to simulate crankshaft location is required when performing this conversion. Some engine builders, such as Keith Dorton of Automotive Specialists, who walked us through this installation process, produce their own with round stock on a lathe, but you can also purchase one from CV Products (PN CV925).
BTW IF YOUR INSTALLING A SINGLE PIECE REAR SEAL ENGINE IN A CAR WITH A PREVIOUS TWO PIECE REAR SEAL ENGINE THE FLYWHEEL OR FLEXPLATE WILL NEED TO BE CHANGED AS THE CRANKS
HAVE a different bolt pattern and the centering hole IN THOSE COMPONENTS is a different size.

onesealvstwo.jpg

Read more: http://www.circletrack.com/enginetech/c ... z2P9IyTMXv

sealrearsur.jpg

don't forget the rear surface of the rear seal to block and main cap needs to be sealed, oil tight
80057.jpg

80063.jpg

rear_main_seal+one_piece_rear_main_oil_seal.jpg


rear_main_seal+seating_alignment.jpg


rear_main_seal+top_adaptor_test_fit.jpg


http://static.summitracing.com/global/i ... daptor.pdf

rear_main_seal+alignment_fixture.jpg
 
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