I recently had my 1957 312 bored .060 over and new cam bearings installed.  When I attempted to install my new Isky E-4 cam it would not even start in the first bearing.  The cam bearing installation appeared okay and Iskyenderian assured me the P/N 301444 cam was the correct one for the 312.  I checked with the supplier where I purchased my overhaul kit and they assured me the bearings were correct and would work in a 292 or 312.  I took the block back to my machine shop and they polished out the bearings so the cam would go in but now the cam feel loose as it goes through the first bearing, yet once installed you have to install the cam gear inorder to turn the cam.  I've heard that some of these parts are made in China and now I wondering if I should get another set of cam bearings and start over.  Anyone had this problem?

buddy

That problem shows up from time to time. It's possible you have inferior off shore bearings like you mention, (there have been reports of soft bearings) because usually the problem shows up beyond the first journal. However, in some cases there is an alignment problem in the block or the cam casting is not straight. Check the cam in two planes with a known good straight edge. If the block openings are not true, then it will need line boring (if you can find a shop that can do it?) or there is a procedure of scraping the bearings on their high spots. Let us know what you find & someone here can help you further.

Paul

I wouldnt be panicking about most of the theorys, my thoughts are alignment during fitting or slight bruising of an edge, which if scraped properly will allow cam to turn freely. sometimes the cam may need the gear on it to give some leverage to get it to turn and if not solid will be ok after a few more turns. I have an old cam with angled grooves cut into journals and relieved on back edge and trims any high spots while being rotated.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

What brand are the cam bearings?

 

If that front bearing ends up being removed, then mic the cam hole in the block without the bearing and insure the hole is within specification.  If you’re having trouble with all the cam bearings in regard to fit, then check all the hole sizes.  Undersized holes will make for a tight clearance when a standard sized cam bearing is being used.  Scraping the bearings seems to be the normal fix but in the extreme cases, remachining the outside diameter of the bearing is the more prudent fix.

 

On a more complicated level is the cam bore alignment in the block.  This would appear to show up more frequently on the 312 blocks but it's rare to see this on the 272/292 blocks.  If this is found during the initial engine assembly, then the bearings can be offset ground on their O.D.’s and clocked appropriately in the block to fix this particular problem.  The other option is re-boring the cam holes to a larger size to insure straightness throughout and custom making a new set of cam bearings.

Lorena, Texas (South of Waco)

Hey guys, thank you all for the great comments and suggestions with my tight cam bearing problem.  My parts supplier has graciously offered to send me another set of Durabond cam bearings at no cost and I will pass the information on to the machine shop.  I'm taking my block to another machine shop that specializes in Y block engines.  I will let you all know what it took to remedy this problem. 

buddy

While you still have it apart have you checked the depth of the oil groove in the camshaft?I  dont know about the particular cam you are using but the standard aftermarket(and Ford) cams have too shallow an oil groove.Should be about. 034 for best oil feed to heads.

  

I have a Iskyenderian E-4 cam and the oil grove on the center journal appears to be about .030 wide and only about .015 to .020 deep.  When my new cam bearings come in I'll see if my machine shop can cut the oil grove to .034 deep as you suggested.  Thanks 

buddy

Okay guys, I took my block to another shop to get a second opinion and they said didn't see a problem with where the other shop polished out the cam bearings inorder to make the cam fit.  They said it was not uncommon to have to shave or polish out the new cam bearings to get the cam to fit.  Thanks for the advice from all of you.     

buddy