cam bearing install tools & install info

[grumpyvette]

Youll need a cam bearing installation tool or your local machine shop can install the bearings for you, if your not doing this regularly, have them do it, as its cheaper and easier,on a one time install basis, but if you are doing it frequently GET a decent tool and learn how to use it, keep in mind its MANDATORY that the oil feed holes in the block align with the feed holes in the cam bearings once they are installed,but theres an oil feed groove that is machined in the block under some bearings and may not be under others, be observant, think things through,that must be lined up with the oil feed hole,from an engineering perspective the ideal location for the oil feed holes to provide the max cam journal support are indicated in the diagram posted below and most cam bearing sets come with instructions, in most cases that locates the cam bearing feed hole in the 12o,clock to -2 o,clock location with the block in its normal orientation,THIS IS WHERE THE CAM BEARING MANUFACTURERS SUGGEST YOU INSTALL THE BEARINGS FOR MAXIMUM CAM JOURNAL SUPPORT AND DURABILITY ,AS THIS LOCATION ALLOWS THE MAX OIL WEDGE SUPPORT TO BE FORMED AND MAINTAINED, AS THE ENGINE RUNS, you certainly don,t want the oil feed hole located where the max oil film support needs to be or in a location restricting flow to the bearing, but read thru the links provided, and be aware that the cam bearings are FREQUENTLY a different diam. for at least one and frequently several locations in the block so they must be located in the matched locations

engine building is about 75% technology and science and 10% art, and 15% skill gained through experience,over time.
doing it successfully mandates the person involved, in the process, can accurately observe, think, and recognize problems,
and if required, stop and think up solutions.
yes it involves knowing how components are intended to function and accurate precision measurement and access to some specific tools and a skilled well equiped machine shop you can trust, is a mandatory factor and skill set.
so many guys seem to be under the absurd impression that any and all solutions,
to any and all problems,
invariably involve, throwing away some component,
and installing some new out of the box part,
instead of acting logically and actually measuring,
thinking and potentially custom clearancing or at least reading the instructions,
and as most experienced engine builders will tell you ,
almost nothing you can buy fits and functions correctly in out-of-the-box, condition
,too near its true potential.after its ,
carefully, inspected, and correctly clearanced, and fitted.

Camshaft Bearing Installation - Step by Step

In this video we’ll be taking an in depth look at the process of installing camshaft bearing in a Small Block Chevy. Previous video showing engine disassembl...

www.youtube.com

get into the habit of taking notes, examining details and measuring the cam bearings,.. noticing the location of oil feed holes, and taking pictures and notes, on the outer and inner dimensions and that generally one edge is beveled to make installation easier, note that some cam bearings have a reverse side oil feed groove while other brands do not! notice that the oil feed passages and main cap grooves tend to measure differently and not all bearings fit all locations
taking the effort to be observant, measure , and ask questions rather than just jamming parts in anyplace, will save you from making lots of expensive mistakes

http://www.summitracing.com/parts/cca-5605/overview/

http://www.harborfreight.com/6-piece-telescoping-gauge-set-5649.html

the rear cam tunnel freeze plug?

theres two, sizes
23/32-inch expansion plug or the 47/64ths (cam plug)
or
IF you somehow screw up the install,of the rear cam tunnel freeze plug, by failing to coat the freeze plug with sealant, along its outer edge, before you install it correctly, you can probably knock it out coat it with sealant and re-install it,
but the cost of a new plug is rather minimal and the risk of it failing , if its re-installed, also minimal,but if it was my engine,
yes I'd buy coat and install a new rear cam plug, as having it blow out once the engines installed would be a huge P.I.T.A.
leaving it in place without sealant can be done but you run a slightly higher chance of an oil leak, that would be a P.I.T.A. to fix later on.

this stuff is pretty much interchangeable

the dorman catalog showed both plugs for 62-68 327 & 67 up 350's also.

the small one is dorman # 555-049.
23/32 o.d.,
the large one is 555-080.
47/64 o.d.
just be sure an measure the one you knock out or the hole it fits and use an accurate caliper

http://www.wizardswarehouse.com/products/tools

This does not just apply to just Chevys,
Look closely at the outer side of the back of the cam bearings theres usually a number on the back ,of the bearings, there also usually a small instruction sheet packaged with the bearings listing the outer dia. and the position in the block if the bearings differ in dia., if they do vary in size the rear is normally the smaller bearing
you must align the oil feed holes in the block with the bearing feed holes
on early (1965) bbc engines the rear cam bearing is grooved failure to use a grooved rear cam bearing causes problems on early big blocks
the 1965 and 1966 big block 396 had unique rear cam bearings and required a grooved rear cam journal, most cams you buy currently are not grooved, the groove can be cut on a lathe in the last rear journal on the later cams , centered ,and its about .188 wide and .125 deep, if the cam is cut,for that oil groove the standard cam bearing can be used[/size]

your potential rear cam bearing oil flow issue is found on the 1965- too a few very early 1967 BBC engines ,if you install the older design BBC cam with a grooved rear main in EITHER config with EITHER rear bearing your covered, and since thats just not expensive and any decent machine shop can modify any cam like that cheaply is the smart route to take if your in doubt

http://forum.grumpysperformance.com/viewtopic.php?f=44&t=10360
The correct cam bearings for the engine you have is very impotent some take a grooved rear cam bearing #396 Clevite SH615S 65-66 only!!!
Clevite SH616S 67-93 396-427.

(VERIFY CAREFULLY WITH YOUR APPLICATIONS NEEDS WITH YOUR SUPPLIER)
SBC CAM BEARING PART NUMBERS [/B]
dura-bond CHP-8
ACL 5C3349C
Clevite SH1349S
FM 2100M
Hi-Tech BC290SP
King CS507HP
TAKE THE EFFORT TO MEASSURE AND VERIFY BEARING LOCATIONS AND CLEARANCES
Taken From AERA Pro-Sis
Cam Bearing Bore diamentions
#1 2.0190-2.0210
#2 and #5 2.0090-2.0110
#3 and #4 1.9990-2.0010

(VERIFY CAREFULLY WITH YOUR APPLICATIONS NEEDS WITH YOUR SUPPLIER)
BBC CAM BEARING PART NUMBERS
CHP-12
Clevite SH2144S
FM 2101M
Hi-Tech BC616SP
King CS524HP
Cam Bore: 2.140 inches (number-1), 2.130 inches (number-2 and number-5), 2.120 inches (number-3 and number-4); cam bearing inside diameter: 1.950 inches

(VERIFY CAREFULLY WITH YOUR APPLICATIONS NEEDS WITH YOUR SUPPLIER)
PONTIAC CAM BEARING PART NUMBERS
P-4 standard DUR-PP-4T coated, SOME use PB-9 check carefully
ACL 5C292S
Clevite SH292S
Engine Tech CC416
FM 1220M
Hi-Tech BC292S
King CS511BB
SDI MP109
sealed power 1220M
Camshaft Bearing Set

Part Number CS 511BB STD
For 1963-79 Pontiacengines only.
Cross reference- ACL: 5C292 CLE: SH- 292S DUR: P-4 FMO: 1220M

Positions 1 through 5

• cam journal diameter- 1.8992"/ 1.8997"

• cam tunnel bore- 2.0297"/ 2.0317"

• cam bearinglength- 0.6800"

• maximum wall thickness- 0.0644"

You can see from the specs above the cam bearings are basically identical

https://www.summitracing.com/search...-installation-and-removal-tools/universal/yes

shop carefully cam bearing tools sell for $40-$300 plus and almost identical tools car vary in price by over $120, and be awre all cam bearings in a single block may be different sizes based on the location, so pay attention as you remove them as to the oil feed hole location(S), how they are indexed or clocked and the outside diameter and be aware in many cases the bearing is beveled on one side to aid installation

Keep in mind chevy cam bearings are NOT interchangeable to all locations in the block, read the instructions and measure the bearings and the install location

download/file.php?id=2011

http://www.rodandcustommagazine.com/tec ... g_oil.html

By placing the bearing's oil hole at roughly the 2:00 position (anywhere between 2:00 and 3:00 is fine), oil is fed into the clearance between the cam journal and cam bearing as the cam rotates clockwise, creating an oil wedge that travels down and supports the cam much better during cam rotation. This forces a superior oil wedge under the cam, to provide oil support at the bottom (6:00) position.

with the block in its normal operational position
any oil needed will easily travel thru the passages and grooves,on the back side of the cam bearing, obviously if theres no oil groove in the rear of the bearing shell or block you have zero choice but to align the oil feed to the cam bearing oil feed holes. I would keep the bearing feed holes as previously indicated if these a oil feed groove.
many cam bearings and many blocks are grooved to provide oil flow to the bearing feed holes, direction of the feed flow to the bearing is less important than maintaining the oil wedge under the cam journal at the area of max loads


REMEMBER the pressure in any portion of an hydraulic system is equal throughout that system., your oil pump will maintain pressure and oil flow to the bearings, changing the flow direction of the oil feed passages has little effect

big block chevy cam bearing installation - Google Search

If there's the groove in the block under the cam bearing, it provides the route pressurized oil takes around the bearing that feeds oil to location past that point in the oil distribution,and supplies the feed to the cam bearing, the ideal oil feed is indicated in the upper diagram, if there's no groove in the block under the bearing, your forced to line the holes in the block that feed oil up to the bearing, to the holes in the bearing, or bearing feed hole location.

any and all of the rear 4 bearing oil feed holes will work located in the 12-to-2 0.clock location
looking at the block from the front in its normal operating orientation with the oil pan down, heads on top
the front bearing , feeds back into the lifters so the diagram below may help clarify this, in fact some guys drill a third hole
and locate the bearing holes with a 10-,12,-2 o.clock hole location, the reason this is done is that if you bust a push-rod and the lifter gets thrown clear of its lifter bore (which while rare does happen) all the lifters farther fore ward in the block on that side ,of the block, drop to a lower oil pressure reading without that reverse oil feed, modification being installed,helping to maintain flow to the lifter feed oil passage,, and while its not going to be perfect it will help during the few seconds it takes you to realize the engine in trouble
[/color]
pontiac

chevy is similar but the cam bearing locations are noty all interchangeable on chevy

I get asked all the time if you can re-used cam bearings, well its your call but I feel its a dumb move to do so, if you have the engine out and your refurbishing it, the oil passages should be cleaned anyway,any time you have the block stripped its almost a mandatory task to replace cam bearings and clean out oil passages, any time you damage a cam bearing its best to replace it as and surface damage tends to result in lower oil pressure and less bearing support, remember theres easily 1000-2000 ft lbs of valve spring pressure on those cam bearings at all times, so if you can,once you've inspected a damaged cam bearing, Id replace that, damaged cam bearing,(S) you've put too much effort and money into doing things correctly to use a damaged cam bearing, the cost of a full set, even if you damaged new bearings during the engine assembly process ,that youll need too get, is just not that high, neither is it difficult to replace , with the engine out of a car on an engine stand,and yes it will drop your oil pressure a bit if left damaged, I don,t know how much it would reduce the pressure but for something that cheap and easy to replace I would NEVER even consider using it in that condition.

usual cost of about $32
http://www.summitracing.com/parts/AAF-A ... /?rtype=10

http://www.summitracing.com/parts/CLE-S ... refilter=1
READ THRU THIS LINK

http://www.dura-bondbearing.com/Portals ... lletin.pdf

http://www.mellingdurabond.com/Portals/ ... arings.PDF

Optimum Placement Of Camshaft Bearing
Oil Feed Hole Location
The AERA Technical Committee offers the following important information on
optimum placement of camshaft bearing oil feed hole location during installation.
This information should be considered any time camshaft bearing replacement is
being done.
Maximum camshaft support will be realized by installing the cam bearing oil feed
hole to the optimum clock location. Blocks and heads using a 360° oil groove
located behind the bearing oil feed, allow one to move the clock position of the cam
bearing oil feed hole. This way you can adjust the clock position during cam
bearing installation to make sure that the optimum location for the best
hydrodynamic wedge is selected. Locating and installing the cam bearing to take
advantage of this hydrodynamic wedge will supply the maximum support for the
camshaft during engine operation. The direction of camshaft rotation and the
engine oil entry point into the bearing control the placement of the hydrodynamic
wedge.
Note: If the oil feed passage in the block or head is just a hole without a 360°
groove, the bearing oil hole must line up with the oil feed passage in the block or
head. In some instances, the bearing oil feed hole in the cam bearing also lines up
with a groove cut in the camshaft journal. In those instances, the location of the
bearing oil feed hole in the bearing is also very critical fore and aft and may not
match up 100% with the hole in the block or head.
The illustration in Figure 1 below shows the optimum engine oil feed hole location

with the block in its normal operational position
(oil pan at the 6 0,clock location)
place the cam bearings in the blocks cam bore exactly like the picture shows
the groove on the back helps to eliminate the total loss of oil reaching the cam journals if it is indexed into the block incorrectly, but having the oil flow enter at the top 1/3rd of the rotation provides the best possible hydraulic oil film. load support

Its generally a very poor idea to locate the oil feed hole at the bottom or 6 ),CLOCK as thats where the oil wedge needs to be the strongest and where the oil feed will be most restricted due to thousands of pounds of valve spring loads on the cam core, trying to seal off the oil feed hole, placing the bearing oil feed hole at between 12 o,clock and 2 o,clock provides the largest possible clearance and oil flow rate plus allows the full 180 degrees of the bearings lower surface to support the cam journal

in a properly set up block a pressurized oil film supports the cam and main bearings
heres the block with the oil pan mounting surface at 12 o,clock or upside down, look at the correctly located oil feed holes in the cam bearings, notice they match the diagram, and two red arrows that show where the dual oil feed holes should be, on bearings with only one feed hole the 12 o,clock to 2 o,clock oil feed hole index is correct, the load is mostly on the cam bearings lower 180 degrees so you sure don,t want oil film strength lowered in that area, by having a oil feed hole that can act like an oil pressure release point in some conditions, you want a maximum thickness oil wedge formed under and supporting the cam journal

be aware both the sbc and bbc engines may not have the block machined for an oil feed groove under the cam bearings in some locations

use of a camshaft install handle generally reduces the chances of damaged cam bearings

VERIFY,SOME DART AFTERMARKET BLOCKS DON.T USE OEM CAM BEARINGS
http://www.speedwaymotors.com/Dart-DT-1T-Cam-Bearings-for-Little-M-Chevy-Block-Set-5,24164.html

http://www.lislecorp.com/uploads/instru ... 726DB5.pdf

http://www.kmjent.com/cart/product.php?productid=597 (good value)

http://www.dura-bondbearing.com/Portals ... lletin.pdf

http://www.pbw-india.com/theory.htm

MAIN BEARINGS FEED FROM THE CAM BEARINGS SO LINING UP OIL FEED HOLES IS CRITICAL

most blocks only have the outer or end cam bearing journals grooved under the cam bearings making proper indexing of the oil feed holes on the 3 inner cam bearings critical, some blocks don,t even have those outer block cam bearing locations grooved

any time you go to install new cam bearings in an engine you first take detailed notes and a few pictures of the OLD cam bearing in the block under good lighting to note the location of the oil feed holes and and grooves, then as they are removed you number them each as its removed and measure them as on many engine they are NOT INTERCHANGEABLE between all main cap locations

http://www.amazon.com/Competition-Cams- ... B000A8MQFY

the tool Ive had and used for DECADES, it works reasonably well.
but check around for a used one in good condition, I bought mine at a chevy swap meet for $80


http://www.lislecorp.com/divisions/products/?product=58
http://www.lislecorp.com/uploads/instructions/18000_WebInstr_CC56DD9726DB5.pdf

keep in mind that I was recently quoted these prices for a cam bearing install, at about $110 a set installed it won,t take long to justify buying a decent cam bearing tool
Cam bearings $ 30.00
Cam bearing remove & install $75.00

https://www.summitracing.com/search...toview=SKU&sortby=Default&sortorder=Ascending

http://www.summitracing.com/search/?key ... tool&dds=1

http://www.summitracing.com/search/?key ... ings&dds=1

http://books.google.com/books?id=G2kUib ... q=&f=false

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

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

http://www.jegs.com/i/Proform/778/66794/10002/-1

http://www.rodandcustommagazine.com/tec ... index.html

READ THESE LINKS AND THREADS[/color]

http://www.jegs.com/i/Proform/778/66820/10002/-1

viewtopic.php?f=51&t=125

viewtopic.php?f=54&t=2187&p=5890#p5890

viewtopic.php?f=53&t=2727&p=7078&hilit=magnets+screens#p7078

viewtopic.php?f=51&t=2919&hilit=cleaning+passages+lifters

viewtopic.php?f=53&t=2727&p=7078&hilit=magnets+screens#p7078

http://video.google.com/videosearch?oe= ... Q&start=40

Cam bearing tools

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

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

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


http://www.aptfast.com/Flyer_HowTo_Dir/ ... arings.htm

http://rodcustom.automotive.com/75500/0 ... index.html

the oil holes should be at the 12 oclock-2 o-clock with the block in the normal position and looking from the front with the block right side up,that allows the oil to form a support wedge under the cam load, on a sbc but carefully verify that the oil passages align with the oil holes in the bearings

bearings are frequently numbered,#1 to #5
*1 is the front one ,The cam bearings are just slightly different in diameter, so you have to make sure you install them in the correct order.the diam. are listed in the link below if you got them mixed up, Make sure the oil holes are lined up when you put them in.12 oclock-3 o-clock with the block in the normal position and looking from the front

read thru this link below carefully

http://static.summitracing.com/global/i ... 900130.pdf

QUOTE
CNC BLOCKS N/E"

"We put our cam bearings in at 4 O'clock and we tap our front galley plugs 1/4 inch pipe and use red locktite and snug them up.

We use just a 1/4X18 pipe tap which is a standard tap and it really does not cut a deep thread is why we use the lock tite.

Be careful on the middle plug as you can put the pipe plug in to far and shut the oil off to the front main bearing and number 1 rod bearings. As I have seen that done before."


http://www.midwestmotorsportsinc.com/order_part.php?item=CH8&line=DUR

http://store.summitracing.com/partdetail.asp?part=CLE-SH1349S&autoview=sku

http://store.summitracing.com/partdetail.asp?part=DUR-CH-12&autoview=sku

http://store.summitracing.com/partdetail.asp?part=CLE-SH287S&autoview=sku

http://store.summitracing.com/partdetail.asp?part=FEM-1255M&autoview=sku

http://www.aptfast.com/Flyer_HowTo_Dir/ ... arings.htm

http://www.rodandcustommagazine.com/tec ... index.html

http://www.chevyhiperformance.com/tech/ ... to_03.html

http://members.shaw.ca/ritc1/bearingtool.html

cam bearings are easily swapped IF you have the correct tools but its generally cheaper to have the local machine shop replace them than to buy the correct tool unless your doing the job fairly regularly.
different blocks and bearing locations have slightly different configs,
obviously if theres no oil feed groove under the bearing the oil feed holes must align with the oil feed passages,
with the block in the upright position the cam bearings are fed,
from the upper central cam, or lifter gallery oil passage, look at the diagrams
most cam bearings come with instructions and diagrams.
and yeah it generally helps to look at the old cam bearings and oil feed hole locations, take notes and in most cases re-install the new bearings in a similar fashion.
chevy V8 cam bearings are NOT universally interchangeable between locations

MAIN BEARINGS FEED FROM THE CAM BEARINGS SO LINING UP OIL FEED HOLES IS CRITICAL

carefully measure the old cam bearings and pay attention to oil feed hole locations
the bearings are not universally interchangeable and yes size varied

http://www.toolsource.com/universal-...l-p-67768.html

if you have access to a lathe you can fabricate a tool for your application for under $20 in parts a 36" section of 1/2" thread rod a couple washers and nuts and a custom turned bearing holder made on the lathe will do the job
BTW its common for the bearings to be different sizes at different locations,some are numbered, some may require the oil feed hole location to differ, etc, so measure the bearings,take note of the oil hole locations on the old cam bearing before you remove them, don,t just take one, new one randomly out of the package and start beating it into place
Ive even seen parts from these kits

http://www.harborfreight.com/cpi/cta...emnumber=35555

http://www.harborfreight.com/cpi/cta...emnumber=92387

http://www.harborfreight.com/cpi/cta...emnumber=95853

used to install them

read thru this link below carefully

http://static.summitracing.com/global/i ... 900130.pdf

DART BLOCKS HAVE A DIFFERENT OIL ROUTE

yes its potentially possible that an oil passage is blocked, by an improperly installed oil passage plug,
or a cam bearing was improperly installed, or a oil passage plug simply popped out due to oil pressure, you might want to try use of a different brand oil filter,
some are much better quality than others and several people have had similar issues;
that were corrected by simply swapping to a different and better quality oil filter

http://garage.grumpysperformance.co...ilter-you-sellect-does-make-a-differance.117/

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

look through the link's and pictures carefully

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

http://garage.grumpysperformance.com/index.php?threads/bearings-and-oil-flow.150/

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

http://garage.grumpysperformance.co...oil-passages-and-improved-oil-flow-mods.3834/

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

the engine needs to come out to replace cam bearings because the rear cam tunnel freeze plug needs to be removed for tool access

in a properly set up block a pressurized oil film supports the cam and main bearings
oil flows around the outer bearing in the groove in the back of the bearing and the matching groove in the cam journal cut in the block

JEGS 80597: Cam Bearing Tool Set for Installation & Removal of Camshaft Bearings - JEGS

Order a cam bearing tool set online. The cam bearing install tool set has everything you could need for camshaft bearing maintenance. Our camshaft bearing tool kit comes with expanding driver, a drive bar, and more. Buy your cam bearing tool set from JEGS High Performance today!

www.jegs.com

Cam bearing install 396 bbc pt1

This is the way i do it and has worked for me so if im doing it wrong let me know thanks.

www.youtube.com

HERES A GUY THAT FEELS A FAR MORE RIGID STAND IS A BIGGER ADVANTAGE THAN HAVING IT FOLD UP SMALLER FOR EASY STORAGE

http://www.northerntool.com/shop/tools/ ... _200305213

READ THIS LINK AND ITS SUB LINKED INFO

IT durability thats KEY in building a good engine

when ever I get into a discussion with many of the guys I build engines for, the younger guys especially seem to be captivated or primarily focused on the concept of having " a RADICAL CAM, that rumbles at idle, or the new brand X heads that some magazine is pushing in the latest engine build...

garage.grumpysperformance.com

 

[grumpyvette]

Cam Bearing And Installation - Under Pressure

viewtopic.php?f=51&t=1479&p=9346&hilit=tool+bearings#p9346

http://www.rodandcustommagazine.com/tec ... index.html

https://www.harborfreight.com/engine-brush-kit-20-pc-63732.html

FAILURE TO READ THESE TWO LINKS MAY COST YOU TIME AND MONEY
IF YOU HAVE A 283 or 265 READ THIS NOW
http://garage.grumpysperformance.co...getting-much-oil-to-rockers.11405/#post-52279

IF YOU HAVE A 1965-1966 big block engine READ THIS NOW
http://garage.grumpysperformance.com/index.php?threads/1965-66-396-engines.10360/#post-42658

Even if the block has been solvent-washed, be sure to wash the block thoroughly, inside and out, using hot, soapy water and soft, clean brushes (small "rifle" brushes can be used to clean oil passages). Rinse the block completely and dry it using compressed air; make sure that all oil and cooling passages are thoroughly blown dry. Immediately afterwards, coat all surfaces with light oil to prevent surface rusting.

Next, you'll need to install the crankshaft main caps, tightening all main cap bolts to specification. Since the main caps will be installed and torqued during final assembly anyway, it's best to have the main caps in place and fully tightened prior to inserting the cam bearings and cam, just in case any distortion occurs within the block due to main cap bolt clamping. Basically, tightening the main caps before messing with the cam serves to pre-stress the block closer to its final state. If any distortion is present, it's better to find out now rather than later.

Before installing cam bearings, wipe all cam bores with a fast-drying solvent to create a clean and dry bore surface. Installation of cam bearings into the block must be done carefully to avoid shaving material from the outside diameter of the bearings. This galling action can easily cause a buildup of excess material between the bearing and the block's bearing bore, which will "squeeze" the bearing, resulting in oil clearance reduction at the bearing inside diameter.

Before attempting to install the cam bearings, make sure that the leading edge of each bearing bore features a slight chamfer (25-30 degrees) to ease bearing installation. Depending on the engine, the cam bearings may be "stepped" (different size for each cam bore) or they may feature the same bore size, front to rear. If the bores are stepped, arrange the cam bearings in the order in which they are to be installed. Remember, when installing cam bearings, always work your way from the rear of the block forward.

On engine blocks that do not feature an oiling groove on the bearing bores, it is vital that each cam bearing is installed in the correct clock-position, so that the bearing's oil hole accurately aligns with the cam bore oiling hole. If the cam bore features a groove, the bearing should be installed with its oiling hole placed at the 2:00 position (when viewed from the front of the block that features clockwise rotation).

Cam Bearing And Installation - Under Pressure
Beating Those Bad Bearing Blues
February 24, 2009
By The R&C Staff
0411 RODP 01 Z BEARING

Cam Bearing Selection And InstallationThe task of replacing camshaft bearings during an engine rebuild may appear to be a no-brainer, but the more intelligent approach is to handle the job with as much planning and precision as you would when replacing main or rod bearings. If not, your engine is likely to wind up with a damaged camshaft and/or main and rod bearings in a relatively short period of time.

"Simply knocking out the old bearings and installing fresh ones with little regard to bearing selection, sizing, or alignment is a big mistake," says Jeff Schaerer, Engine Bearing Product Development manager at Clevite Engine Parts. "For example, ill-fitting cam bearings can result in too little or too much oil clearance, which can damage both the camshaft and/or main and rod bearings. If excessive cam bearing clearance exists, a severe reduction in oil pressure can result in insufficient oil delivery to the rest of the motor."

Mindful of the critical role that proper cam bearing selection, sizing, and alignment can have on engine longevity and performance, let's compare the attributes of two different types of materials commonly used in cam bearing construction. By doing so, you'll be in a better position to determine which type of cam bearings best meet your performance needs.

Bearing SelectionClevite's Schaerer explains that in previous years, the vast majority of cam bearings were manufactured with a "babbitt" lining. Babbitt is a soft, slippery material composed primarily of lead and tin. This soft material does an excellent job of being able to withstand particle contamination and less-than-ideal lubrication on initial engine startup. However, performance engines often operate at higher temperatures and feature higher valvetrain loads, which places babbitt material at a disadvantage. These operating conditions sometimes result in fatigue or deformation (extrusion) of the soft babbitt material.

In order to address higher loads and temperatures, babbitt, for the most part, has been replaced with an aluminum alloy. This specially developed alloy is much stronger than babbitt and can withstand much higher loads. The trade-off lies in the fact that aluminum alloy is harder than babbitt but is less forgiving with regard to contamination, cam bearing bore misalignment, and less-than-ideal lubrication. The benefits of aluminum cam bearings, however, far outweigh the compromises. You simply need to pay more attention to details when installing aluminum cam bearings and be certain to verify critical tolerances.

Traditional babbitt is designed to withstand approximately 1,800 psi of load. By contrast, Clevite's AL-3 material has been designed to withstand up to 5,000 psi. Schaerer says extra oil grooves are not needed with the AL-3 bearings, providing yet another benefit: the bearing affords a larger "footprint" at the cam bore wall, which more efficiently transfers heat away from the bearing. In addition to bi-metal aluminum cam bearings they've also developed tri-metal bearings that combine the strength of aluminum alloy with a babbitt overlay. The tri-metal bearings are able to withstand loads in excess of 8,000 psi.

Cam Bearing InstallationIf you're planning to work on an engine block that has been newly reconditioned, you'll definitely need to replace the camshaft bearings, as the old bearings must be removed beforehand to allow the block to be properly cleaned. The following can be used as a guide for installing cam bearings properly.

The installation process begins after you've accomplished any machining that might be needed (cylinder boring and/or honing, align-honing, deck resurfacing, cam bore alignment, etc.). Before starting, make certain that the block is totally clean. If it's not, then foreign particles trapped between the bearings and bearing bores will cause bearing deformation and reduce oil clearance.


By placing the bearing's oil hole at roughly the 2:00 position (anywhere between 2:00 and 3:00 is fine), oil is fed into the clearance between the cam journal and cam bearing as the cam rotates clockwise, creating an oil wedge that travels down and supports the cam much better during cam rotation. This forces a superior oil wedge under the cam, to provide oil support at the bottom (6:00) position.

As a case in point, earlier small-block Chevy blocks might feature only an oil-feed hole that aligns with the main cap oil passage, in which case the cam bearing's oil hole must align with the saddle's oil hole. By comparison, the '92-97 Chevy LT1/LT4 features a full-circle oil groove, which might lead you to think that exact clock position of the cam bearing oil hole is not important (since oil will feed into the space between the bearing and cam journal and will travel along this groove, eventually feeding into the bearing's hole anyway). However, even if a full-circumferential groove is present, as we mentioned earlier, it is necessary to position the cam bearing's oil hole at a specific position (at approximately the 2:00 position as viewed from the block front) in order to allow cam rotation to create a slight oil "wedge" during operation. This more efficiently creates an oil film between the cam journal and its corresponding bearing. Also, if the oil holes in a full-groove-type setup are aligned exactly (oil hole in the bore saddle and oil hole in the cam bearing), oil pressure can potentially feed-back, momentarily preventing oil from traveling around the journal, which can minimize the necessary oil wedge.

Cam Bearing And Installation - Under Pressure

When fitting aluminum cam bearings, it's important to allow sufficient bearing-to-camshaft clearance, since the harder aluminum alloy bearings won't wear in as rapidly as babbitt bearings to make their own clearance. Minimum clearance should be 0.002 inch for stock engines and 0.003-0.004 inch for high-performance engines.

Our Clevite bearing expert stresses that you should not apply oil to the block's camshaft bores or to the outer diameter of the cam bearings. The cam bearings must feature a dry installation at the block's cam bores. Schaerer also says to make sure you have the proper tools for installing the cam bearings. For example, he recommends using a dedicated cam bearing driver tool, which is available from any engine specialty tool supplier.

At this point, Schaerer says to apply a coating of lubricant to each of the cam bearing's exposed face (the inner diameter of the bearings where the cam will ride). You can use either clean engine oil or, preferably, dedicated engine assembly lube. "A quality assembly lube will cling to the bearing faces better than oil," explains Schaerer. "Granted, you'll be lubing the camshaft's journals prior to inserting the cam anyway, but it never hurts to protect the bearings while you have access to them. Think of it as a bit of added insurance, just in case you should forget to apply lube to one or more of the journals."

Ensuring Optimal Bearing FitWhen replacing cam bearings, it's a good idea to check camshaft-to-bearing fit, even if you purchased your car new, and this is the very first time you are replacing its cam bearings. Clevite's cam bearing expert explains why: "Many rebuilders and do-it-yourselfers are unaware that original equipment engine manufacturers (OEMs) may sometimes install unfinished-size cam bearings into the block, and then machine the cam bearing inside diameters in order to establish correct size, shape and alignment," says Schaerer. "In the industry, this is referred to as 'finished in place,' or FIP, cam bearing installation.

"During the rebuilding process, FIP bearings are removed and replaced with precision cam bearings that have already been manufactured to size," explains Schaerer. "While replacement cam bearings are manufactured to precise tolerances, it is still advisable to check camshaft-to-bearing fit so as to identify potential camshaft journal diameter variances among the replacement camshafts."

If cam fit is too tight, bearing material can be removed by reaming. Schaerer says that honing bearings to size is not recommended, because honing stone grit can easily be trapped in the bearing surface, and its presence there can lead to premature camshaft journal wear.

Another method of "shaving" cam bearings to accept the camshaft journals involves the use of a modified spare/old camshaft of the same application, provided that the old cam's journals are within original diameter specification. In this instance, you begin by cutting a diagonal groove across each camshaft journal, about 1/8-inch deep, then relieve the journal surface on one side of each groove, thereby creating a single cutting edge on one side of each groove.

This modified camshaft is then inserted and used as a reamer. Afterwards, you'll need to attach a used cam sprocket to the cam and carefully turn the cam by hand, in the direction of normal engine rotation, in order to cut clearance in the new bearings.

Clevite's bearing expert says there are also other variables to consider when replacing cam bearings. Casting shifts, for example, can occur in a cast-iron or cast- aluminum block as the block "seasons" during its initial use. The block can become distorted due to temperature extremes (overheating) and improper cylinder head installation where excessive or unequal cylinder head fastener tightening had occurred.

if the oil flow came through the push rods as you primed the engine, in that order your rear cam bearing may not be correctly indexed/installed incorrectly, BOTH the front and rear cam bearings feed oil across to the other lifter gallery when the front and rear cam bearings are correctly indexed to the lifter gallery oil feeds

http://garage.grumpysperformance.co...all-tools-install-info.1479/page-2#post-35245
THE REAR CAM BEARING AND MAIN OIL FEED CENTER OIL PASSAGE AND BOTH LIFTER GALLERY'S ARE FED FROM THE REAR MAIN BEARING AND OIL PUMP THRU THE GROOVE UNDER THE REAR CAM BEARING AND HOLES INDEXED IN IT, ALONG WITH THE READ MAIN CRANK BEARING FED FROM THE CAM BEARING DIRECTLY ABOVE AS ARE ALL THE MAIN BEARINGs

THE FRONT CAM BEARING ALLOWS OIL FLOW TO CROSS OVER ANND FEED BACK DOWN THE OTHER LIFTER GALLERY

NOTICE THE FRONT BEARING FEEDS OIL FROM BOTH SIDES

notice the cam bearing groove feeds both lifter gallerys
LATER SBC ENGINES MODIFIED THE OIL FEED

as these gentlemen do a great job explaining your issue WITH THE EARLY SBC OILING with pictures
"Farm boy" The slot in the original camshaft in out of my 265 is .510” X 1.2” and centered in the middle of the rear journal. A local machine shop had no trouble cutting a slot in a replacement cam.

While you have the cam out you should check the position of the rear cam bearing. You can check it with a tape measure. The front edge of the bearing should be 20¼ inches from the cam sprocket thrust surface on the front of the block. The rear edge of the cam bearing should be 21¼ inches. If the cam bearing is less than 1 inch long it not the correct bearing with two oil holes. If the bearing is the correct 1 inch bearing, but is installed too shallow or too deep, the oil holes in the bearing won’t line up with the machined slot in the camshaft and the lifters won’t get any oil. Hopefully your cam bearing is the right one and is installed at the correct depth.

"
"f.i.57chevynut"]In your original post you didn't mention if the 283 style camshaft was a hydraulic or a solid. The factory notches that are shown in all the previous posts are for hydraulic cams. If the cam was an original solid lifter 55-56 the notch was very small.

obviously the small groove is intended to flow extra oil volume to the rear vertical thrust bearing surfaces

If your not getting oil to the rockers but have 65 psi as the engine idles,
Id suspect either the cam bearings (especially the rear cam bearing or the oil passage plugs under the timing chain are incorrectly installed

in a properly set up block a pressurized oil film supports the cam and main bearings
oil flows around the outer bearing in the groove in the back of the bearing and the matching groove in the cam journal cut in the block

The cam on the left is a factory 210-225 HP solid lifter cam. Since solids didn't need oil to operate, the notch allowed enough oil to lube the tip of the pushrod, rocker ball socket and tip of the valve. Since the oil delivery is impulse rather than full time flow, the 55-56 lifters didn't restrict the flow from the lifter. In 57 the lifter was redesigned to restrict the flow because the oil flow was constant. So if you have original 55-56 lifters you don't want to make the cam bearing a full time flow as it will flood the top end with oil. The full time internal oiling with the later lifters never changed after 57
( on small blocks. 65-66 big blocks had a full grooved camshaft. Go figure.).
The easiest way to install your rear cam bearing is to line up the holes in the block with the holes in the bearing checking the alignment with a nail or wire. That will put it at the correct depth to align with the notch in the cam."

"Farm boy" "f.i.57chevynut" The easiest way to install your rear cam bearing is to line up the holes in the block with the holes in the bearing checking the alignment with a nail or wire. That will put it at the correct depth to align with the notch in the cam.[/quote]
Driving the rear cam bearing in until the holes in the bearing are lined up with the holes in the block won’t guarantee the cam bearing is installed at the correct depth. Notice that the oil holes in the block are much bigger than the holes in the bearing. It is possible to have the cam bearing holes aligned with the large holes in the block but not be fully exposed to the slot in the cam. In fact if the rear cam bearing in a 265 is installed as little as 1/8 inch off the oil supply to the lifters will be cut off. For proper oiling the rear cam bearing must be aligned with the slot in the rear cam journal.

"
\\ RELATED INFO THAT YOU PROBABLY NEED TO READ

http://garage.grumpysperformance.co...er-lifter-install-direction.11398/#post-52227

http://garage.grumpysperformance.co...ed-holes-in-bearings-shells.10750/#post-46966

http://garage.grumpysperformance.co...all-tools-install-info.1479/page-2#post-35245

http://garage.grumpysperformance.com/index.php?threads/1965-66-396-engines.10360/#post-42658

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

 

[grumpyvette]

Cam Bearing And Installation - Under Pressure

Just as a block's main bores can become out of round or misaligned (creating the need for align-boring or align-honing), the cam bores can be subjected to similar geometry changes. This is why camshaft fitment problems sometimes occur when dealing with a used block. However, with a little patience and a close attention to detail during the cam assembly, you can readily overcome such problems.

Correcting Cam Bore AlignmentIf the cam bores need to be aligned, it is possible to enlarge them to establish bore roundness and front-to-rear bore alignment. However, remember, when you enlarge the cam bores, you will also need to address the difference created by the larger bores. This is accomplished by installing oversize-o.d. cam bearings or by sleeving the larger bores to accept standard o.d. bearings.

Due to the popularity of the small-block Chevrolet engine in performance applications, Clevite offers special oversize-o.d. cam bearings that permit align-boring the block's cam bores to one size (matching the No. 1 cam bore, which is the largest cam bore in the block). These oversize-o.d. cam bearings are available in both +0.010- and +0.020-inch sizes.

Clevite's SH-1352S cam bearing kit includes five bearings that are all the same size. Blocks must be bored to 2.029-2.031 inches (0.010 inch larger than the original No. 1 cam bearing bore). The Clevite PN SH-1401S cam bearing kit includes a +0.020 inch oversize, requiring cam bores to be bored to 2.039-2.041 inches.

In addition, Clevite offers a third cam bearing option for small-block Chevrolet engines, PN SH-1528S. These are special tri-metal bearings that feature a +0.010-inch oversize o.d. for cam bores that have been enlarged to 2.029-2.031 inches. These premium tri-metal bearings, though priced higher than aluminum alloy bearings, offer a thin electroplated babbitt overlay for improved bearing surface properties in combination with the high strength of aluminum alloy.

Installing The CamshaftOnce all of the cam bearings have been installed, you're ready to tackle the job of placing the camshaft into position. If the camshaft is new, it is usually safe to assume that the shaft is straight. However, if you plan to install a used camshaft, be sure to check it for runout. Begin by resting the camshaft on its front and rear journals, on clean V-blocks. Next, place a dial indicator at the center cam journal. Preload the gauge at about 0.050 inch, then zero the gauge. Slowly rotate the camshaft a full 360 degrees, noting the runout on the indicator. "Generally speaking, if the cam shows more than 0.001 inch of runout, it should not be used, because the slightest bit of runout beyond this point will likely create a fitment problem," says Schaerer.

Remember to clean the camshaft thoroughly before installation. Cleanliness is critical, so take your time, making absolutely certain that the camshaft is clean and free of any foreign particles.

The next step is to coat the cam, using the type of camshaft assembly lube specified by the camshaft maker (this is often included in a camshaft kit). "Coat the whole stick," says Schaerer in reminding us to apply the lubricant to the entire camshaft, including the cam gear, journals, and lobes.

Now you're ready to install the camshaft. Keep in mind that it is very fragile. The camshaft must be inserted slowly, taking care to avoid dragging the lobes across the bearing faces. Any scratches or nicks can result in unwanted escape paths for oil, which will lead to insufficient oil pressure at the cam bearing locations. It's advisable to use a special camshaft installation tool to ease this task. The tool attaches to the cam nose and provides a convenient handle to help in guiding the cam into the bores while maintaining better control of the cam angle.


at times having a long small diameter light that you can stick through the blocks oil passages to check the oil feed to the bearings passage alignment helps

https://www.tooltopia.com/steelman-...MI4s7coYzY2AIV3I2zCh3U6AFUEAQYAiABEgI0PfD_BwE
Cam Bearing And Installation - Under Pressure

You'll need to carefully insert the camshaft into the cam bores until fully seated, but don't push too far as you might dislodge the rear soft plug at the rear cam bore opening. Since the crank is not in the way at this stage of the installation, you'll have convenient access to the rear of the cam, which you can use to help guide the stick through the bore holes.

Once the cam is fully inserted (be sure all journals are centered on their respective bearings), rotate the camshaft by hand to check for fit. The camshaft should turn easily. A slight bit of resistance is acceptable. If you find the camshaft is difficult to turn, however, you may have one or more bearings that are too tight on the i.d. (inner diameter). In that case, carefully remove the camshaft and check each bearing for any sign of a burr at the front or rear edge.

If a burr is found, you can trim the edge burr with a deburring tool. However, Schaerer adds a word of caution, saying, "If you do this, don't get too carried away. A very slight trim is all that's needed." Afterwards, clean the area, re-insert the cam, and once again check the fit.

In any performance engine, it's always a good idea to "degree" the camshaft in order to verify the timing of valve opening and closing. For performance purposes, it may be necessary to retard or advance the camshaft timing in order to increase low-end or high-end engine performance. While we don't have room in this article to address camshaft degreeing, the steps involved in this procedure can be obtained from the camshaft maker's instruction sheets or on the cam maker's Web site.

LiftersYou should always install new lifters along with your new camshaft. This is especially important when dealing with a "flat-tappet" solid or hydraulic camshaft, since lifters rotate during operation and establish distinct wear patterns at each camshaft-lobe-contact area. If you're working with roller lifters, however, you may re-use them as long as they are in good condition and are appropriate for the specific replacement camshaft. In any case, make certain that the components you are using are compatible. Always use flat-tappet solid lifters with a flat-tappet solid lifter cam, flat-tappet hydraulic lifters with a flat-tappet hydraulic cam, and roller lifters with a roller camshaft.

Though it's not recommend, if you choose to install used flat-tappet lifters, do so only if the original flat-tappet camshaft is also being installed. In this scenario, it is vital that each lifter location matches the original installation. If you're planning to reuse the original cam and lifters, inspect them carefully to make sure they are in good condition. Remember, too, that the lifters must be mated only to the specific cam lobe to which they were mated originally.

"Flat"-tappet lobes and lifters are only "flat" to the eye. In reality, each lobe features a slight taper, approximately 0.001 inch to 0.007 inch. Each lifter also has a slight crown. This combination of a tapered lobe and domed lifter face is a design feature that causes the lifter to rotate in its bore during engine operation, enabling it to avoid concentrated scuff wear.

Regardless of the type of lifters being installed, you are advised to coat each lifter liberally with the proper type of assembly lubricant before insertion. If roller lifters are being installed, each lifter must be guided (via a lifter guide bar) in order to place the roller tip in alignment with the cam lobe, and to prevent the lifter from rotating in its bore. If a roller lifter rotates in its bore, severe lifter and camshaft damage will occur. Always check each lifter in its bore for smooth up-down movement, and also confirm that each flat-tappet lifter will rotate smoothly in its bore.

Now you're ready for the finishing touches. With lifters in place, install the pushrods and adjust the valve lash according to the engine manual or the cam maker's instructions. Avoid "over-rolling" the engine, to minimize loss of cam lubricant from lobes and lifter faces.

Camshaft "Break-in"If the camshaft and lifters feature a flat-tappet (solid or hydraulic) design, camshaft break-in is absolutely critical to camshaft longevity. It's also important to make every effort to ensure that the engine will start during the first attempt.

Once the engine has fired, keep it running and immediately bring engine speed to within 1,500-2,200 rpm, especially if a flat-tappet cam and lifter system is employed. Maintain engine speed within that range, varying up/down, for about 20 minutes. This will help to properly "seat" rings, bearings, and the camshaft/lifters. If an engine with a flat-tappet camshaft and lifters is operated below about 1,500 rpm during the initial run, there may not be sufficient oil lubrication to the cam lobe/lifter contact areas to allow the lifters to rotate.

Increased oil pressure resulting from elevated engine speed helps the lifters to rotate, rather than scuffing against the lobes in a locked (non-rotating) position. If the lifters are not lubricated properly and don't rotate during this first run, they can initiate a wear path at the lobe, which will quickly damage the cam lobe(s). "Don't kid yourself about this," says Schaerer. "If the engine is insufficiently lubricated at the lifter-to-lobe contact area, you can cause permanent damage to the lobes and lifter within a few seconds of startup, and you can destroy a flat-tappet camshaft and its lifters in less than a minute."

If the cam and lifters are of the roller design, where each lifter features a roller bearing at its camshaft lobe contact, camshaft break-in is much less demanding (some will argue that roller cam break-in is simply a non-issue). That's because instead of the lifters scuffing across the cam lobes while trying to establish a mating pattern, roller lifters "roll" across the lobes, virtually eliminating any lobe/lifter frictional mating concerns. Nonetheless, it's still wise to elevate the initial run for a few minutes, even when dealing with a roller cam setup, if only to ensure that the oil pressure is sufficient to aid in the lifter roller-tip operation.

Clevite's Schaerer offers this final bit of advice, "The golden rule that applies to starting up a fresh motor is simple: Slow down and take your time in carefully performing a complete pre-flight check. Remember, any extended period of cranking can cause oil to be wiped from critical load bearing surfaces, such as cam lobes and lifters. The goal is to achieve smooth engine startup on the first try."

 

[NYH1]

I just ordered a cam bearing installation & removal tool from Summit yesterday. When I had the machine work (and new cam bearing installed) done on my block I was planning building a 350. I got a little extra cash so I bought a 383 Scat Rotating assembly. I did the rod/block clearance work myself, which was no big deal. Now I want to removing the cam bearings to clean the block better and make sure no metal shavings are behind the cam bearings. My machinist is very busy now, plus I want to do as much work on my block/motor as possible .

I planned on marking each one of the bearings with a black marker to note their "clock position" in the block before I remove them. Then install them to the same position after I clean everything. Does this sound correct?

 

[grumpyvette]

THIS IS WHY OIL FEED HOLES SHOULD BE IN THE 12-2 o,clock location
thats a good idea, just be aware that they differ in diameter in some locations, so number each bearing and make notes on both the bearing location and how the oil supply holes located

http://www.autozone.com/autozone/repair ... le=replace

look thru all the linked info but study this

http://static.summitracing.com/global/i ... 900130.pdf





NOTE
Some engines, such as the small block Chevrolet V-8, have a rear cam bearing bore that is wider than the bearing. Failure to correctly align the bearing oil hole, in the rear cam bearing to the blocks oil feed groove can result in a total loss of oil pressure in this engine.

the location of the oil holes effects the OIL WEDGE and LOAD SUPPORT EFFICIENCY

theres a GROOVE UNDER THE CAM BEARING SO IT CAN BE INSTALLED WITH THE HOLES IN ANY LOCATION,(2 0,clock is generally preferred) but some locations offer greater load support.(5 O,clock to -8 O,clock is the worst) and not all bearing will fit all locations, because they are not the same diameter, and some don,t have the same number of oil feed holes

I looked into doing installing roller cam bearings when I built my current corvette 383 as I was sure going into the build that it would be a good idea, but once I really researched the costs of the machine work, parts and special cams etc. it rapidly became obvious that on anything used mostly for transportation or drag racing its pissing money down a rat hole compared to a dozen other options you could spend the money on. the process involves having a machine shop bore the block cam tunnel larger, for the larger roller bearings , installing them and using a larger custom made cam, between the the cost of the cam, bearings and machine work you can easily spend $600-$900 on the upgrade, now if I was racing at SEBRING or the 24 hours at daytona where the engine would be under max stress 70%-90% of the time, theres no question that the idea has SOME merit, as would the billet roller cam and larger and stiffer cam core, allowing larger cam lobes and .904 chrysler style roller lifters, which while not mandatory are a good idea on an endurance application.
the lower friction cam bearing are supposed to give you about 3-4 extra hp and reduce oil temps a couple degrees , and reduce friction but the main gains are in the larger bearing size that allows larger cam lobes and reduced lifter acceleration rates, less cam flex and a more stable valve train

"Typical steel-backed lead babbit cam bearings do an excellent job in everyday use but have a number of shortcomings in severe-duty applications. First, in many engine designs, oil is routed from the oil pump to the cam, then to the main bearings, and then to the rod bearings, in that order. In a highly stressed mill, it should be the other way around. The rotating assembly spins twice as fast as the cam and is much more heavily loaded than the cam journals.

Second, whenever radical cam profiles are used, so too are high-pressure valve springs. As they maintain order within the valve train, stiff springs also create plenty of extra friction between the lifters and cam lobes. This is transferred directly to the cam bearings where accelerated wear can result.

Finally, there is the issue of oil temperature. We all know that petroleum-based motor oil can break down if things get too hot. Eliminating much of the friction caused by the spinning cam yields a measurable decrease in oil temperature for added longevity and safety.

All three potential problems are eliminated when you switch to rollerized cam bearings. It eliminates the oil flow leakage around the cam bearings, providing full volume to the rotating assembly, and the superior construction of the roller bearings will handle up to 900 pounds of valve-open spring pressure without problems. (Numbers over 1,000 pounds can be tricky, but youÂ’ll never go there unless youÂ’re fielding a Pro Stocker.) The reduced friction can drop oil temperature by as much as 20 degrees, allowing dry sump users to carry and pump less oil.

Are rollerized cam bearings for you? If your motor lives life one quarter-mile at a time, probably not. The block machine work, cam bearing kit, and specific camshaft can cost upward of $700. You could spend the money more effectively elsewhere. But if you stay on it for miles on end, roller cam bearings are a definite engine-saver. Typical users include Bonneville racers, Silver State entrants who run WFOT for 90 miles, and Sprint Car racers who run balls-out for 30 laps. WeÂ’d be remiss if we didnÂ’t mention the end-all endurance crazies of NASCAR. Every last one of them relies on rollerized cam bearings. In this story, Gene Ohly and Jaime Gonzalez of Evans Speed show us the right way to enjoy the benefits of rollerization."
you must use a billet cam core, if not the roller bearings will chew up the softer material.
Read more: http://www.hotrod.com/techarticles/bonn ... z1tQnpcQXr

http://www.compcams.com/catalog/COMP201 ... 12_374.pdf

http://www.summitracing.com/parts/CCA-5412/

http://www.hotrod.com/techarticles/bonn ... s_install/

http://www.performanceblocks.com/CNC_En ... rsion.html

PN 350RCB from Comp Cams. http://www.summitracing.com/parts/CCA-350RCB-KIT/

Roller Cam Bearings For Maximum Endurance
This comparison demonstrates the superior load-bearing capacity of the needle bearings. The larger outside diameter necessitates machining the cam housings and cam tunnel. The altered inside diameter also requires a camshaft with specifically matched journals. Make sure you get in touch with a cam-grinder who can supply you with the right cam before you permanently modify your block.

CNC BLOCKS POSTED THIS
"We do a lot of cam tunnel blue print work and the babbit cam bearings seem very common among engine builders today,

Look at the LS type engines they have bigger cam journals and higher rocker ratios.

As mentioned the babbit cam bearing take away unwanted harmanics out f the vavle train and the cam is floating on a film of oil VS having oil in the needle bearings which you may have up to 50 or more needle bearings per bearing and tring to roll all those needles in oil does take more power now times 5 roller bearings

Plus the bigger cam cores don't flex or twist like the smaller journals do which is a big plus.

We machine alot of 010 block with the BBC cam tunnels for mostly flat tappet engines as we can run 1.8 and 1.9 rocker ratios with out tearing the nose of the cam off.

Going with a 60MM cam core will require special bushings that are taller so the oil band on the lifter does not come up out of the lifter hole and because the oil band is higher in the lifter bore it also requires a higher grove in the bushing as the oil band on the lifter is higher then oil feed holes.

55MM cam cores are most common with the BBC and most guys are using the babbit cam bearings P/N Durabond GMP-55-T which requires a 2.283 housing bore which takes a roller cam bearing in the same housing bore.

If you step up to the 55MM cam core I would suggest going to the .904 lifters with the bigger wheel which is like having an extra half a point of rocker ratio, You must let your cam grinder know what size wheel your using as the bigger wheel pick up on the ramp earlier and leaves later.

And the .904 uses a bigger body and bigger wheel and axel make for a much dependable lifter plus going with a bigger cam core is much easier on the lifters.

There are pretty good gains going with a bigger cam core from the feed back I have gotten from other engines builders we have done work for. "

 

[NYH1]

My father, my son (8) and I used the cam bearing tool tonight to remove my cam bearings. It was pretty easy. I think installing them after I clean the block will be pretty easy as well. It's installing the rear freeze plug behind the rear cam bearing that I'm worried about.

The rear freeze plug at the end of the cam tunnel is what determines how far the cam sits in the block right? How do I set the correct depth?

 

[grumpyvette]

I think your making a major mistake if you don,t replace the cam bearings and flush out the block passages
new cam bearings are less than $20 in most places
example
http://www.summitracing.com/parts/DUR-CH-8/

http://www.summitracing.com/parts/SUM-173000/

you can buy or rent the tool to install them
http://www.summitracing.com/parts/SUM-900130/

remember the rear cam tunnel freeze plugs not a 2" freeze plug its something like 2 1/32"
http://www.summitracing.com/parts/DRT-3 ... 5.7L%2f350

notice theres a SLIGHT STEP the plug seats against in most cases the rear of the plug seats even with the block surface
IVE always seated the plug edge just level with or a bit deeper than flush with the back of the blocks plug recess boss and found that works, remember to use a brush on sealant on the plug edge, and use a punch in three places to lock it in place

viewtopic.php?f=57&t=869&p=1357&hilit=+sealant#p1357

keep in mind the GROOVE under the cam bearing must aline with the oil feed hole in the bearing

Got Cam Bearing Problems?
After hearing about a fellow sprint car racer’s bearing troubles with two of his engines, I asked a few questions and thought I might know his problem. Upon looking at his block (GM 3970010 Chevy), I knocked the cam bearings out and found what I expected.

The oil passage drilled from the main bearing bore to the cam bearing was a 1/4˝ diameter passage like always but the passage from the main galley to the cam bearing bore was only 3/16˝ diameter. This, I believe was a contributing factor in his bearing problem.

Our shop has always checked this passage during disassembly and taken a 6˝ X 1/4˝ drill bit and drilled that passage on every Small Block Chevy, whether it was street or race application. Most early 265, 283 and 327s have the 3/16˝ diameter passage. Some 307, 327 and 350s also have the 3/16˝ diameter passage. Just make sure which diameter that oil passage is while you have the cam bearings out and if it’s the small one take that moment to take a drill and 6˝ X 1/4˝ dia. bit (as it will reach all the way through from the main bore) bit to open it up to 1/4˝.

I also check the depth of the groove that passes the oil around the cam bearing at that time. If it’s a race engine I like it to be at least .200˝ wide X .125˝ deep for adequate oiling.

Norm Johns

 

[NYH1]

So I take it that the timing chain gear on the cam controls how far the cam go into the block?

 

[grumpyvette]

So I take it that the timing chain gear on the cam controls how far the cam go into the block?

the depth is controlled both by the cam button,placed in the center hole of the cam gear,(either chain or gear drive) keeping the cam from moving forward and the back of the cam gear, and constant oil pressure behind the cams rear end from moving to the rear,thats one reason Ive always suggested drilling the front pass side oil passage plug with a #64 drill so extra oil is constantly sprayed on the rear of the cam gears to limit wear, between the cam timing set and the blocks front cam bearing boss.
allowing for extra oil spraying onto the timing chain assembly by drilling small holes in the forward oil passage plugs is an old engine builders mod that even the factory in some rare cases used.
its simply a reasonable way to get extra lubricant to the timing chain assembly, which because its spinning tends to throw off oil rapidly so its in constant need of more oil flow. its designed to get most of its oil in the form of a constant oil fog in the crank case,generated by the spinning rotating assembly and theres a larger upper hole in the block wall and the oil pan forward section that allows oil to slosh onto the timing chain when you hit the brakes, but unless your running right up at the full mark on the dip stick that oil sloshing tends to be limited, so adding the hole to the oil passage forward plugs tends to help.

https://www.harborfreight.com/6-piece-telescoping-gauge-set-5649.html

https://www.homedepot.com/p/General-Tools-12-in-Inside-Caliper-454-12/202545173?cm_mmc=Shopping|THD|G|0|G-Pro-PLA|&gclid=EAIaIQobChMI6J6Lq8Si2AIVlbrACh1ZWQfYEAQYAiABEgI5TfD_BwE&gclsrc=aw.ds&dclid=CLqo4rHEotgCFVLZwAod5HoAtg

viewtopic.php?f=27&t=1170

a number #64 or #65 drill is about correct

you may want to READ THESE again
viewtopic.php?f=54&t=2187

viewtopic.php?f=52&t=1793&p=4553&hilit=button+cam+cover#p4553

viewtopic.php?f=52&t=282

viewtopic.php?f=52&t=181

viewtopic.php?f=52&t=90

viewtopic.php?f=53&t=2209&p=6925#p6925

http://www.summitracing.com/parts/CLO-9 ... /?rtype=10

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

http://www.summitracing.com/parts/CCA-202/

http://www.summitracing.com/parts/CCA-200/

http://www.summitracing.com/parts/CCA-4605/

http://www.summitracing.com/parts/PJJ-327-1C/?rtype=10

 

[grumpyvette]

paint the cast surfaces

yes the stuffs expensive and high quality,
try to have a buddy go in for 50% of the cost,
a quarts easily enough for 5 -7 engines,
if you look at it, as a durability enhancement, thats less than $10 an engine
https://www.eastwood.com/glyptal-re...MIlvW7u4TQ4gIViLrACh0WFgRnEAQYAiABEgLLafD_BwE

Ive used it and seen several other people use it , it works fine.
glyptal is used to seal in, micro surfaces and prevent fine metallic dust,
that might be present ,
even after a blocks been cleaned,
from getting into the oil flow circulating back to the oil pump,
if the blocks clean, grease free and dry when its applied ,
and if its left to dry over night it will not come off.

 

[grumpyvette]

I can see where building a custom cam bearing tool would not be overly difficult

obviously if your mechanically inclined and have access to a lathe, building your own cam bearing installation tool to be used to draw the bearings into place using a 24" section of 1/2" thread rod is just not that difficult to do, you need a bearing holder like the diagram above, and a couple large fender washers and youll need a couple thread nuts , but its hardly a difficult concept, to use the threads to draw the bearing holder into the block to seat the bearing in the block recess, carefully read the previous linked info in this thread
the tools use is more a tweak or refinement than mandatory, but increasing cool lubricant flow to the lifter contact area can,t hurt a bit!I bought mine simply because I liked the idea, and its proved to be useful.
I usually groove my blocks lifter bores lower 1/3rd regardless of the lifter type used, but Id point out that the grooves are shallow and designed to flow extra cooling lubricant, so you'll want to also use a windage tray to control the extra coolant flow volume.
I don,t think they are as big a benefit to roller cam applications, as the flat tappet lifter applications but obviously your more or less stuck with the grooves in the lifter bores even if you change lifter types after the lifter bores grooved unless you sleeve them.

The cam bearings are just slightly different in diameter, so you have to make sure you install them in the correct order. The smallest in back, largest in front. Make sure the oil holes are lined up when you put them in


Tips for Maximizing Cam Bearing Performance in High Performance and Stock Engines

For many years, nearly all camshaft bearings were manufactured with a lining of babbitt. Babbitt is a soft slippery material made up primarily of lead and tin and is quite similar to solder. As a bearing surface layer, babbitt possesses the desirable properties necessary to survive under adverse conditions such as foreign particle contamination, misalignment and marginal lubrication on start up.

The trend in modern engines has been toward higher operating temperatures and higher valve train loads. Babbitt is limited in its ability to survive under these conditions due to its relatively low strength. When babbitt cam bearings are installed under these demanding conditions, the lining may extrude or fatigue. Fatigue can be identified by craters in the bearing surface where sections of lining material have flaked out.

To meet the demands of higher loads and operating temperatures in modern engines as well as the requirements imposed by high performance, babbitt has been replaced by an alloy of aluminum. This aluminum alloy is much stronger than babbitt and will withstand several times the load which causes babbitt to fatigue or extrude. However, this added strength is obtained at the expense of some of the more forgiving properties of babbitt. The aluminum alloy is harder, making it somewhat less compatible with dirt, misalignment and marginal lubrication. This is typical of the compromises or trade offs that are frequently necessary when selecting a bearing material to suit the requirements of a specific application and in this case, higher loading.

Typically, whenever a higher level of loading is encountered, greater precision is required to maintain reliability. Conditions such as cleanliness, alignment, clearances, journal surface finishes and lubrication must all be controlled more closely. Following are some recommendations to help optimize performance when using aluminum alloy camshaft bearings.

Sufficient clearance is necessary in the initial installation. These stronger bearings will not wear in rapidly to make their own clearance like softer materials. Minimum clearance should be .002" for stock engines and .003" for high performance. Optimum clearance range for high performance applications is .003" to .004". Because of the stack up of tolerances on the block, shaft and bearing it is impossible to control clearance to this range in the manufacture of the bearing alone. Clearances must be measured at installation.

Honing the ID's of cam bearings to increase clearance is not recommended because hone grit may become embedded in bearing surfaces which will cause shaft wear. Bearing ID's may be reamed, but the most practical means is to adjust camshaft journal diameters by grinding. Even if not ground to provide additional clearance, camshaft bearing journals should be polished to a surface finish of 10 micro-inches Ra or better with the camshaft rotating in the same direction it will rotate in the engine.

Like clearance, alignment is also extremely important especially for high performance applications. Any block that has needed to have its main bearing bore alignment corrected due to distortion is likely to have experienced cam bearing bore distortion as well. Adequate clearance will help compensate for minor misalignment of less than .001". Special cam bearing sets with oversize outside diameters are available for Small Block Chevrolet engines to allow align boring the camshaft bearing housing bores in these engines. SH-1352S contains 5 bearings which are all the same size. Blocks must be bored to 2.030/2.031" (.010" larger than the original #1 position) in all 5 positions. Similarly, SH-1401S offers a .020 oversize (2.040/2.041" housing bore).

A third special cam bearing set also available for the small block Chevy is the SH-1528S. These are special trimetal bearings with .010" oversize OD for blocks align bored to 2.030/2.031". These premium trimetal parts are priced higher than the aluminum alloy parts but offer the added advantage of a thin electroplated babbitt overlay for improved bearing surface properties in combination with high strength.

Installation of bearings into the block must be done with care to avoid shaving metal off the backs of the bearings. This galling action may cause a build-up of metal between the bearing OD and the housing bore which will result in a reduction in clearance. To prevent galling, check housing bores for a proper 25 to 30 degree lead-in chamfer before installing cam bearings. On blocks without grooves behind the cam bearings, care must be taken to insure that oil holes line up between the bearings and block. Where the block has a groove behind the bearing, the bearing should be installed with the oil hole at the 2 o'clock position when viewed from the front for normal clockwise camshaft rotation. This will introduce oil into the clearance space outside of the loaded area and allow shaft rotation to build an oil film ahead of the load.

Clean the block and all components thoroughly. Hot water and detergent are best for cleaning blocks, crankshafts and camshafts to remove grit from honing, grinding and polishing. After cleaning, blow dry and coat with oil immediately to prevent rusting. Coat all bearing surfaces with Clevite Bearing Guard and all camshaft lobes and lifter faces with Cam Guard to provide a prelubricant to these critical surfaces. It is also recommended that engines be primed by externally driving the oil pump or pressuring the system externally through the pressure sensing port before initial start up. Engines should be operated at approximately 1500 to 2000 RPM for the first 15 minutes to insure proper lubrication during the initial stages of break in.

I have a 1966 396. Rebuild ongoing and time to select a cam. I know the '65 and '66 have the groove in the rear journal. The machine shop cut a groove on the outside of my rear bearing (like a '67 396) when they installed the new ones. When shopping, most cams start at 1967 (I assume because of the groove). So the question is, can I now buy a 1967 camshaft? Is the groove the only difference is the basic question.
thanks

be sure when your prepping the block,
pressure clean the block with a good grease solvent

http://www.homedepot.com/p/Simpson-Hond ... 177499-_-N

and high pressure water,
rinse and dry the block, clean the internal oil passages with a rifle bore brush,

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

and cover the machined surfaces with a good quality rust preventative

a high pressure air hose and extended nozzle

and a heat gun help the process.

paint the cast surfaces

ive used it and seen several other people use it , it works fine
the 1965 and 1966 big block 396 had unique rear cam bearings and required a grooved rear cam journal, most cams you buy currently are not grooved, the groove can be cut on a lathe in the last rear journal on the later cams , centered ,and its about .188 wide and .125 deep, if the cam is cut,for that oil groove the standard cam bearing can be used

this is a diagram of the big block chevy oil passage system, its designed to feed that rear cam bearing in the center, the groove in the rear cam journal forms the walls of the oil passage cutting an additional groove, in front of the rear freeze plug behind the back cam bearing in the rear of the last cam bearing is unlikely to hurt or help as long as that groove is cut in the cam journal, I've always just cut the groove in the rear cam journal on the 65-66 engines and never had any issues, in fact I know several guys who do that mod on later engines that don,t require it, because they think it helps maintain slightly better oil flow rates to cool the valve train.
OBVIOUSLY if you want too test you manually prime the oil pump ,if you get decent oil flow volume at all the rockers,priming the engine oil pump manually, then obviously the oil flow leaving the pump reaches the intended areas and the route it takes while a bit different than originally designed may still work and not cause you any issues, keep in mind that as the engine rpms increase the oil flow rate needs to the valve train need to increase also and while it may be possible, to machine a shallow groove, in a later rear cam bearing it won,t be able to allow nearly the required oil flow rate at higher rpms as the rear bearing shell is just not thick enough,to allow a deep enough groove on the early engines, those engines, require the early rear cam bearing with the three hole aligned correctly and the grooved rear cam journal, some shops will modify the later cam bearings, installed in early blocks by cutting a large bevel in the rear edge, to allow oil to flow behind and around the rear cam journal, this is not always 100% successful, at providing full oil flow capacity on the early engines that don,t have the block grooved under the rear cam bearing ,especially at higher rpm levels.

RELATED INFO
viewtopic.php?f=54&t=985&p=18690&hilit=prime+distributor#p18690

viewtopic.php?f=54&t=2187

personally Id use a grooved rear cam journal and correctly indexed grooved three oil hole ,rear cam bearing on the early engines,(see pictures below) but they are becoming rather scarce and the newer engines and aftermarket blocks don,t have this issue

later blocks had a groove cut under and around the outside and behind the cam bearing for oil to reach the valve train, similar to this picture below

’65-’66 Big-Block Lifter Gallery Oiling: In order to feed pressurized oil to the galleries that feed the lifters, the ’65-’66 big-blocks used a combination of a groove in the rear cam journal and a rear cam bearing with a matching groove on its inside diameter. Oil entered the bearing through a hole at the bottom, traveled around the journal through the groove in the bearing and the journal, and exited the bearing through two holes at the top that aligned with two holes in the block; those two holes fed the oil galleries on each side that fed the lifters. Both the cam journal and the cam bearing MUST have the groove in order to provide adequate oil flow to the lifters, and the bearing must have the two exit holes at the top.

’67-Up Big-Block Lifter Gallery Oiling: Starting in 1967, Chevrolet redesigned the oiling path to the lifter galleries. The groove was removed from both the rear cam journal AND from the I.D. of the rear cam bearing, and an annular groove was machined into the rear cam bearing bore in the block instead. With the smooth rear journal and cam bearing surfaces, oil entered the bearing through the same hole in the bottom, but part of it flowed around the outside diameter of the cam bearing, through the groove machined in the bearing bore, and exited through the same two holes in the block at the top that fed the lifter galleries. The cam bearing now had only one hole, at the bottom.

What This Means To You: Your block dictates what you can use. The 1967 non-grooved cam and non-grooved one-hole rear bearing will NOT work in a ’65-’66 block, period; you need the cam with the grooved rear journal and the rear cam bearing with the three holes and the groove on its I.D. The cam isn’t a big problem – any competent machine shop can cut the required groove in the rear journal of the camshaft, and all you need then is the correct rear cam bearing, which will be included with a ’65-’66-only big-block cam bearing set.

Photo below is the '67-up rear cam bearing, with only one (inlet) hole at the bottom and no groove; the rest of the oil goes around the OUTSIDE of the bearing shell (through the annular groove machined in the bearing bore in the block), to feed the two lifter gallery holes at the top of the bearing bore. '65-'66 3-hole grooved bearing also shown for comparison.

on the early big blocks oil from the oil pump enters the rear cam bearing at 6 0,clock travels around both sides of the rear cam journal and exits into both lifter oil feed gallery passages at about 10 o,clock and 2 o,clock to feed the lifters

on the later big blocks oil from the oil pump enters the rear cam bearing at about 2 0,clock travels around both sides of the rear cam journal and exits slowly thru bearing clearances but the vast majority of the oil flow from the pump travels around the outside of the bearing thru the groove in the block the routes oil directly to the lifter gallerys on both banks into both lifter oil feed gallery passages at about 10 o,clock and 2 o,clock to feed the lifters

 

[grumpyvette]

"GRUMPYVETTE?
I pulled my Old cam of my engine to install my new cam and timing set,

I found the Cam bearings looked worn and have some scuff marks

Can I replace the cam bearings when the motor still in the car and Do they make a tool for that?"

THIS is a good example of what happens to bearings if the oil passages are allowed to push small metallic debris, from wear like rockers,valve tips,cam and lifter wear thru the engine, use of a few small magnets, and shrapnel screens helps reduce or eliminate this

cam bearings are only sold in complete sets.
BTW they are not all the same and not interchangeable in location or oil hole indexing in most cases
the cam bearing should all be replaced if ones worn significantly and that will generally require the block being out of the car on an engine stand, as most of the common cam bearing tools used to install the cam bearing require the rear cam tunnel freeze plug being removed for access

http://static.summitracing.com/global/images/instructions/sbc cam bearing position info.pdf

http://www.summitracing.com/parts/SUM-173000/

heres some related info, READ THE LINKS

Id be concerned that any cam bearing damage was not limited to a single location, ID suggest inspecting them and heres an inspection tool to do it with


http://www.toolrage.com/prodview.asp?sku=SLI-PV300

http://forum.grumpysperformance.com/viewtopic.php?f=50&t=1513&p=3556&hilit=tool+inspect#p3556

http://www.google.com/products/catalog? ... IMBEPMCMAA

http://www.tooltopia.com/atd-tools-8620 ... lebase_18u

http://www.summitracing.com/parts/AAF-A ... /?rtype=10

http://www.summitracing.com/parts/CLE-S ... refilter=1

READ THIS THREAD AND SUB LINKS, pay especial attention to the location of the oil feed hole locations and the fact that bearing locations are not interchangeable
viewtopic.php?f=51&t=1479

I know this will sound absolutely crazy, but I purchased the tool above (in the read case) decades ago for $45, that tool now sells for $170 and while it works great,and it works on almost any engine or bearing size Ive also used a custom fabricated hand made , cam bearing tools like this one pictured below , that my dad made on a lathe for me for less than $20 and at least 4-5 other tools and they all work, so ID just get the cheap one or make your own if you have lathe access, but a 24" long section of 3/4" thread rod is a better choice than a smaller diam.
the cheap ones generally push the bearing into place once its aligned with a few hammer taps, the more expensive ones generally use a threaded rod to draw the bearing into place giving a more precise placement but with practice either style tool works, just be aware that on many engines the bearings are NOT interchangeable for all locations in the block as sizes vary

http://www.hotrodders.com/forum/home-ma ... 35881.html

http://garage.grumpysperformance.com/index.php?threads/cam-degree-equipment-tools.1759/#post-4440

 

[LEJ ZO6]

I still have one of the Snap-On cam bearing install tools for sale if anybody is interested in aquiring one. They are a high quality tool and work on almost any engine.

viewtopic.php?f=88&t=4551

https://autoplicity.com/5674772-com...ng-installer?gclid=CLyHyIfsiNQCFYZDhgodLREBjA

 

[grumpyvette]

the pictures of your cam install tool no longer show?

 

[grumpyvette]

the pictures of your cam install tool no longer show?
can you repost those?


RELATED ARTICLES
http://www.rodandcustommagazine.com/tec ... ewall.html

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

Cam Bearing Selection And InstallationThe task of replacing camshaft bearings during an engine rebuild may appear to be a no-brainer, but the more intelligent approach is to handle the job with as much planning and precision as you would when replacing main or rod bearings. If not, your engine is likely to wind up with a damaged camshaft and/or main and rod bearings in a relatively short period of time.

"Simply knocking out the old bearings and installing fresh ones with little regard to bearing selection, sizing, or alignment is a big mistake," says Jeff Schaerer, Engine Bearing Product Development manager at Clevite Engine Parts. "For example, ill-fitting cam bearings can result in too little or too much oil clearance, which can damage both the camshaft and/or main and rod bearings. If excessive cam bearing clearance exists, a severe reduction in oil pressure can result in insufficient oil delivery to the rest of the motor."

Mindful of the critical role that proper cam bearing selection, sizing, and alignment can have on engine longevity and performance, let's compare the attributes of two different types of materials commonly used in cam bearing construction. By doing so, you'll be in a better position to determine which type of cam bearings best meet your performance needs.

Bearing SelectionClevite's Schaerer explains that in previous years, the vast majority of cam bearings were manufactured with a "babbitt" lining. Babbitt is a soft, slippery material composed primarily of lead and tin. This soft material does an excellent job of being able to withstand particle contamination and less-than-ideal lubrication on initial engine startup. However, performance engines often operate at higher temperatures and feature higher valvetrain loads, which places babbitt material at a disadvantage. These operating conditions sometimes result in fatigue or deformation (extrusion) of the soft babbitt material.

In order to address higher loads and temperatures, babbitt, for the most part, has been replaced with an aluminum alloy. This specially developed alloy is much stronger than babbitt and can withstand much higher loads. The trade-off lies in the fact that aluminum alloy is harder than babbitt but is less forgiving with regard to contamination, cam bearing bore misalignment, and less-than-ideal lubrication. The benefits of aluminum cam bearings, however, far outweigh the compromises. You simply need to pay more attention to details when installing aluminum cam bearings and be certain to verify critical tolerances.

Traditional babbitt is designed to withstand approximately 1,800 psi of load. By contrast, Clevite's AL-3 material has been designed to withstand up to 5,000 psi. Schaerer says extra oil grooves are not needed with the AL-3 bearings, providing yet another benefit: the bearing affords a larger "footprint" at the cam bore wall, which more efficiently transfers heat away from the bearing. In addition to bi-metal aluminum cam bearings they've also developed tri-metal bearings that combine the strength of aluminum alloy with a babbitt overlay. The tri-metal bearings are able to withstand loads in excess of 8,000 psi.

Cam Bearing InstallationIf you're planning to work on an engine block that has been newly reconditioned, you'll definitely need to replace the camshaft bearings, as the old bearings must be removed beforehand to allow the block to be properly cleaned. The following can be used as a guide for installing cam bearings properly.

The installation process begins after you've accomplished any machining that might be needed (cylinder boring and/or honing, align-honing, deck resurfacing, cam bore alignment, etc.). Before starting, make certain that the block is totally clean. If it's not, then foreign particles trapped between the bearings and bearing bores will cause bearing deformation and reduce oil clearance.

Even if the block has been solvent-washed, be sure to wash the block thoroughly, inside and out, using hot, soapy water and soft, clean brushes (small "rifle" brushes can be used to clean oil passages). Rinse the block completely and dry it using compressed air; make sure that all oil and cooling passages are thoroughly blown dry. Immediately afterwards, coat all surfaces with light oil to prevent surface rusting.

Next, you'll need to install the crankshaft main caps, tightening all main cap bolts to specification. Since the main caps will be installed and torqued during final assembly anyway, it's best to have the main caps in place and fully tightened prior to inserting the cam bearings and cam, just in case any distortion occurs within the block due to main cap bolt clamping. Basically, tightening the main caps before messing with the cam serves to pre-stress the block closer to its final state. If any distortion is present, it's better to find out now rather than later.

Before installing cam bearings, wipe all cam bores with a fast-drying solvent to create a clean and dry bore surface. Installation of cam bearings into the block must be done carefully to avoid shaving material from the outside diameter of the bearings. This galling action can easily cause a buildup of excess material between the bearing and the block's bearing bore, which will "squeeze" the bearing, resulting in oil clearance reduction at the bearing inside diameter.

Before attempting to install the cam bearings, make sure that the leading edge of each bearing bore features a slight chamfer (25-30 degrees) to ease bearing installation. Depending on the engine, the cam bearings may be "stepped" (different size for each cam bore) or they may feature the same bore size, front to rear. If the bores are stepped, arrange the cam bearings in the order in which they are to be installed. Remember, when installing cam bearings, always work your way from the rear of the block forward.

On engine blocks that do not feature an oiling groove on the bearing bores, it is vital that each cam bearing is installed in the correct clock-position, so that the bearing's oil hole accurately aligns with the cam bore oiling hole. If the cam bore features a groove, the bearing should be installed with its oiling hole placed at the 2:00 position (when viewed from the front of the block that features clockwise rotation).

By placing the bearing's oil hole at roughly the 2:00 position (anywhere between 2:00 and 3:00 is fine), oil is fed into the clearance between the cam journal and cam bearing as the cam rotates clockwise, creating an oil wedge that travels down and supports the cam much better during cam rotation. This forces a superior oil wedge under the cam, to provide oil support at the bottom (6:00) position.

As a case in point, earlier small-block Chevy blocks might feature only an oil-feed hole that aligns with the main cap oil passage, in which case the cam bearing's oil hole must align with the saddle's oil hole. By comparison, the '92-97 Chevy LT1/LT4 features a full-circle oil groove, which might lead you to think that exact clock position of the cam bearing oil hole is not important (since oil will feed into the space between the bearing and cam journal and will travel along this groove, eventually feeding into the bearing's hole anyway). However, even if a full-circumferential groove is present, as we mentioned earlier, it is necessary to position the cam bearing's oil hole at a specific position (at approximately the 2:00 position as viewed from the block front) in order to allow cam rotation to create a slight oil "wedge" during operation. This more efficiently creates an oil film between the cam journal and its corresponding bearing. Also, if the oil holes in a full-groove-type setup are aligned exactly (oil hole in the bore saddle and oil hole in the cam bearing), oil pressure can potentially feed-back, momentarily preventing oil from traveling around the journal, which can minimize the necessary oil wedge.

When fitting aluminum cam bearings, it's important to allow sufficient bearing-to-camshaft clearance, since the harder aluminum alloy bearings won't wear in as rapidly as babbitt bearings to make their own clearance. Minimum clearance should be 0.002 inch for stock engines and 0.003-0.004 inch for high-performance engines.

Our Clevite bearing expert stresses that you should not apply oil to the block's camshaft bores or to the outer diameter of the cam bearings. The cam bearings must feature a dry installation at the block's cam bores. Schaerer also says to make sure you have the proper tools for installing the cam bearings. For example, he recommends using a dedicated cam bearing driver tool, which is available from any engine specialty tool supplier.

At this point, Schaerer says to apply a coating of lubricant to each of the cam bearing's exposed face (the inner diameter of the bearings where the cam will ride). You can use either clean engine oil or, preferably, dedicated engine assembly lube. "A quality assembly lube will cling to the bearing faces better than oil," explains Schaerer. "Granted, you'll be lubing the camshaft's journals prior to inserting the cam anyway, but it never hurts to protect the bearings while you have access to them. Think of it as a bit of added insurance, just in case you should forget to apply lube to one or more of the journals."

Ensuring Optimal Bearing FitWhen replacing cam bearings, it's a good idea to check camshaft-to-bearing fit, even if you purchased your car new, and this is the very first time you are replacing its cam bearings. Clevite's cam bearing expert explains why: "Many rebuilders and do-it-yourselfers are unaware that original equipment engine manufacturers (OEMs) may sometimes install unfinished-size cam bearings into the block, and then machine the cam bearing inside diameters in order to establish correct size, shape and alignment," says Schaerer. "In the industry, this is referred to as 'finished in place,' or FIP, cam bearing installation.

"During the rebuilding process, FIP bearings are removed and replaced with precision cam bearings that have already been manufactured to size," explains Schaerer. "While replacement cam bearings are manufactured to precise tolerances, it is still advisable to check camshaft-to-bearing fit so as to identify potential camshaft journal diameter variances among the replacement camshafts."

If cam fit is too tight, bearing material can be removed by reaming. Schaerer says that honing bearings to size is not recommended, because honing stone grit can easily be trapped in the bearing surface, and its presence there can lead to premature camshaft journal wear.

Another method of "shaving" cam bearings to accept the camshaft journals involves the use of a modified spare/old camshaft of the same application, provided that the old cam's journals are within original diameter specification. In this instance, you begin by cutting a diagonal groove across each camshaft journal, about 1/8-inch deep, then relieve the journal surface on one side of each groove, thereby creating a single cutting edge on one side of each groove.

This modified camshaft is then inserted and used as a reamer. Afterwards, you'll need to attach a used cam sprocket to the cam and carefully turn the cam by hand, in the direction of normal engine rotation, in order to cut clearance in the new bearings.

Clevite's bearing expert says there are also other variables to consider when replacing cam bearings. Casting shifts, for example, can occur in a cast-iron or cast- aluminum block as the block "seasons" during its initial use. The block can become distorted due to temperature extremes (overheating) and improper cylinder head installation where excessive or unequal cylinder head fastener tightening had occurred.

Just as a block's main bores can become out of round or misaligned (creating the need for align-boring or align-honing), the cam bores can be subjected to similar geometry changes. This is why camshaft fitment problems sometimes occur when dealing with a used block. However, with a little patience and a close attention to detail during the cam assembly, you can readily overcome such problems.

Correcting Cam Bore AlignmentIf the cam bores need to be aligned, it is possible to enlarge them to establish bore roundness and front-to-rear bore alignment. However, remember, when you enlarge the cam bores, you will also need to address the difference created by the larger bores. This is accomplished by installing oversize-o.d. cam bearings or by sleeving the larger bores to accept standard o.d. bearings.

Due to the popularity of the small-block Chevrolet engine in performance applications, Clevite offers special oversize-o.d. cam bearings that permit align-boring the block's cam bores to one size (matching the No. 1 cam bore, which is the largest cam bore in the block). These oversize-o.d. cam bearings are available in both +0.010- and +0.020-inch sizes.

Clevite's SH-1352S cam bearing kit includes five bearings that are all the same size. Blocks must be bored to 2.029-2.031 inches (0.010 inch larger than the original No. 1 cam bearing bore). The Clevite PN SH-1401S cam bearing kit includes a +0.020 inch oversize, requiring cam bores to be bored to 2.039-2.041 inches.

In addition, Clevite offers a third cam bearing option for small-block Chevrolet engines, PN SH-1528S. These are special tri-metal bearings that feature a +0.010-inch oversize o.d. for cam bores that have been enlarged to 2.029-2.031 inches. These premium tri-metal bearings, though priced higher than aluminum alloy bearings, offer a thin electroplated babbitt overlay for improved bearing surface properties in combination with the high strength of aluminum alloy.

Installing The CamshaftOnce all of the cam bearings have been installed, you're ready to tackle the job of placing the camshaft into position. If the camshaft is new, it is usually safe to assume that the shaft is straight. However, if you plan to install a used camshaft, be sure to check it for runout. Begin by resting the camshaft on its front and rear journals, on clean V-blocks. Next, place a dial indicator at the center cam journal. Preload the gauge at about 0.050 inch, then zero the gauge. Slowly rotate the camshaft a full 360 degrees, noting the runout on the indicator. "Generally speaking, if the cam shows more than 0.001 inch of runout, it should not be used, because the slightest bit of runout beyond this point will likely create a fitment problem," says Schaerer.

Remember to clean the camshaft thoroughly before installation. Cleanliness is critical, so take your time, making absolutely certain that the camshaft is clean and free of any foreign particles.

The next step is to coat the cam, using the type of camshaft assembly lube specified by the camshaft maker (this is often included in a camshaft kit). "Coat the whole stick," says Schaerer in reminding us to apply the lubricant to the entire camshaft, including the cam gear, journals, and lobes.

Now you're ready to install the camshaft. Keep in mind that it is very fragile. The camshaft must be inserted slowly, taking care to avoid dragging the lobes across the bearing faces. Any scratches or nicks can result in unwanted escape paths for oil, which will lead to insufficient oil pressure at the cam bearing locations. It's advisable to use a special camshaft installation tool to ease this task. The tool attaches to the cam nose and provides a convenient handle to help in guiding the cam into the bores while maintaining better control of the cam angle.

You'll need to carefully insert the camshaft into the cam bores until fully seated, but don't push too far as you might dislodge the rear soft plug at the rear cam bore opening. Since the crank is not in the way at this stage of the installation, you'll have convenient access to the rear of the cam, which you can use to help guide the stick through the bore holes.

Once the cam is fully inserted (be sure all journals are centered on their respective bearings), rotate the camshaft by hand to check for fit. The camshaft should turn easily. A slight bit of resistance is acceptable. If you find the camshaft is difficult to turn, however, you may have one or more bearings that are too tight on the i.d. (inner diameter). In that case, carefully remove the camshaft and check each bearing for any sign of a burr at the front or rear edge.

If a burr is found, you can trim the edge burr with a deburring tool. However, Schaerer adds a word of caution, saying, "If you do this, don't get too carried away. A very slight trim is all that's needed." Afterwards, clean the area, re-insert the cam, and once again check the fit.

In any performance engine, it's always a good idea to "degree" the camshaft in order to verify the timing of valve opening and closing. For performance purposes, it may be necessary to retard or advance the camshaft timing in order to increase low-end or high-end engine performance. While we don't have room in this article to address camshaft degreeing, the steps involved in this procedure can be obtained from the camshaft maker's instruction sheets or on the cam maker's Web site.

LiftersYou should always install new lifters along with your new camshaft. This is especially important when dealing with a "flat-tappet" solid or hydraulic camshaft, since lifters rotate during operation and establish distinct wear patterns at each camshaft-lobe-contact area. If you're working with roller lifters, however, you may re-use them as long as they are in good condition and are appropriate for the specific replacement camshaft. In any case, make certain that the components you are using are compatible. Always use flat-tappet solid lifters with a flat-tappet solid lifter cam, flat-tappet hydraulic lifters with a flat-tappet hydraulic cam, and roller lifters with a roller camshaft.

Though it's not recommend, if you choose to install used flat-tappet lifters, do so only if the original flat-tappet camshaft is also being installed. In this scenario, it is vital that each lifter location matches the original installation. If you're planning to reuse the original cam and lifters, inspect them carefully to make sure they are in good condition. Remember, too, that the lifters must be mated only to the specific cam lobe to which they were mated originally.

"Flat"-tappet lobes and lifters are only "flat" to the eye. In reality, each lobe features a slight taper, approximately 0.001 inch to 0.007 inch. Each lifter also has a slight crown. This combination of a tapered lobe and domed lifter face is a design feature that causes the lifter to rotate in its bore during engine operation, enabling it to avoid concentrated scuff wear.

Regardless of the type of lifters being installed, you are advised to coat each lifter liberally with the proper type of assembly lubricant before insertion. If roller lifters are being installed, each lifter must be guided (via a lifter guide bar) in order to place the roller tip in alignment with the cam lobe, and to prevent the lifter from rotating in its bore. If a roller lifter rotates in its bore, severe lifter and camshaft damage will occur. Always check each lifter in its bore for smooth up-down movement, and also confirm that each flat-tappet lifter will rotate smoothly in its bore.

Now you're ready for the finishing touches. With lifters in place, install the pushrods and adjust the valve lash according to the engine manual or the cam maker's instructions. Avoid "over-rolling" the engine, to minimize loss of cam lubricant from lobes and lifter faces.

Camshaft "Break-in"If the camshaft and lifters feature a flat-tappet (solid or hydraulic) design, camshaft break-in is absolutely critical to camshaft longevity. It's also important to make every effort to ensure that the engine will start during the first attempt.

Once the engine has fired, keep it running and immediately bring engine speed to within 1,500-2,200 rpm, especially if a flat-tappet cam and lifter system is employed. Maintain engine speed within that range, varying up/down, for about 20 minutes. This will help to properly "seat" rings, bearings, and the camshaft/lifters. If an engine with a flat-tappet camshaft and lifters is operated below about 1,500 rpm during the initial run, there may not be sufficient oil lubrication to the cam lobe/lifter contact areas to allow the lifters to rotate.

Increased oil pressure resulting from elevated engine speed helps the lifters to rotate, rather than scuffing against the lobes in a locked (non-rotating) position. If the lifters are not lubricated properly and don't rotate during this first run, they can initiate a wear path at the lobe, which will quickly damage the cam lobe(s). "Don't kid yourself about this," says Schaerer. "If the engine is insufficiently lubricated at the lifter-to-lobe contact area, you can cause permanent damage to the lobes and lifter within a few seconds of startup, and you can destroy a flat-tappet camshaft and its lifters in less than a minute."

If the cam and lifters are of the roller design, where each lifter features a roller bearing at its camshaft lobe contact, camshaft break-in is much less demanding (some will argue that roller cam break-in is simply a non-issue). That's because instead of the lifters scuffing across the cam lobes while trying to establish a mating pattern, roller lifters "roll" across the lobes, virtually eliminating any lobe/lifter frictional mating concerns. Nonetheless, it's still wise to elevate the initial run for a few minutes, even when dealing with a roller cam setup, if only to ensure that the oil pressure is sufficient to aid in the lifter roller-tip operation.

Clevite's Schaerer offers this final bit of advice, "The golden rule that applies to starting up a fresh motor is simple: Slow down and take your time in carefully performing a complete pre-flight check. Remember, any extended period of cranking can cause oil to be wiped from critical load bearing surfaces, such as cam lobes and lifters. The goal is to achieve smooth engine startup on the first try."

 

[elisalvador]

ok ,, after reading the post. i have a 350 i removed the cam bearings, the #1 and #5 bearings were located at the 12 o clok position , #2,3,4, were located on the 6 o clock position , the cam, bearing bores do have a 360 groove on it , so does this mean that i can place the #2,3,4 cam bearings in the 2 o clock position ??? the cam bearings im using are speed pro bearings, and the bearings them selfs do not have a groove behind them,,, just the actual bearing bore has the 360 grooove ,,, thanks

 

[grumpyvette]

If there's the groove in the block under the cam bearing, it provides the route pressurized oil takes around the bearing that feeds oil to location past that point in the oil distribution,and supplies the feed to the cam bearing, the ideal oil feed is indicated in the upper diagram, if there's no groove in the block under the bearing, your forced to line the holes in the block that feed oil up to the bearing, to the holes in the bearing, or bearing feed hole location.

notice in these pictures your looking toward the upper engine from the crank location and the bearing oil feed holes are correct in the upper 1/3rd of the block in the 10 o,clock location to -2, o,clock location

Ideally youll install the cam while the engines on a engine stand while using the correct tool to maximize your ability to guide it into and thru the cam bearings without scratching the soft bearing surfaces, use of a handle that allows control and leverage is a very good idea, and its far stronger than just inserting a long bolt will be. nicks tend to cause wear issues and lower oil pressure and this can effect engine durability

 

[elisalvador]

ok , so does that mean , that how the cam bearings were installed before was on the poor side of the chart? before i removed them ?

 

[grumpyvette]

yes, it means they were not located to provide ideal support, but that doesn't mean they would not work installed that way, only that they would provide less support to the cam under load, and less than ideal oil flow to the bearing surfaces

 

[elisalvador]

oh ok i get it,,, i understand it makes sense , thanks again