cam bearings

[Mearl]

I went to put the cam in the .040 over 350 I'm building for Maxine this afternoon and it wouldn't go past the second bearing. This is the second time it's happened to me; a few years ago I had the same thing happen. That time I warmed up the block with a torch and the cam went in but when it cooled, it wouldn't turn and I broke the end of it off at the index pin trying to turn it. I had tried 2 sets of bearings on that one, I don't know what the hell I'm doing wrong!

 

[Don Jacks]

Same block?

 

[63impalass409]

I had that happen on a 327 I was building but that was a badly nicked cam bearing on the #3 and not sure if it was me or the machine shop. I believe it was the machine shop as they had also told me they turned my last 09 crank 10 under so I bought those bearings for that only come to find out it was only polished and not turned and never needed a turning. Idiots

 

[Jim Sullivan]

Maybe the cam bearing is peened on the front side from driving it in?

 

[blkblk63ss]

I went to put the cam in the .040 over 350 I'm building for Maxine this afternoon and it wouldn't go past the second bearing. This is the second time it's happened to me; a few years ago I had the same thing happen. That time I warmed up the block with a torch and the cam went in but when it cooled, it wouldn't turn and I broke the end of it off at the index pin trying to turn it. I had tried 2 sets of bearings on that one, I don't know what the hell I'm doing .

Heat the block ,,,,, Never heard of that Mearl ?????

 

[Iowa 409 Guy]

I've used dry ice on bushings.

 

[MRHP]

Cam bearings may be a bit cocked in the bore, not unheard if. I guess the cam tunnel could be warped, but not real common of a problem.

 

[Ishiftem]

Is there a burr in the bore? Or maybe like MRHP said. Cam journal oversize? Cheap bearing driver causing issues? If you are 100% sure there is nothing you are doing wrong, you can make a reamer out of an old cam and shave the bearing in place to clearance it.

 

[La Hot Rods]

When installed the front bearing did you install it from the rear? If not it could be the front bearing is not inline with the second one.

 

[Mearl]

Maybe the cam bearing is peened on the front side from driving it in?

Jim, I'm thinking that must be whats happening. The last time, it was a different block and I used 2 sets of bearings before deciding the block must be bad and getting another one. The second one went just fine and is in my 72 Corvette. I think it must be my bearing driver causing a lip.

 

[Mearl]

We use roller burnisher at work on cam bearings, it gets used several times a day, both on small blocks and LS motors. I may bring it home this weekend and see if I can make this work.

 

[La Hot Rods]

Mearl you need to get a picture of that tool for us.

 

[Mearl]

Here you go. We actually have a few different sizes, the ones in the picture are for cam bearings and lifter bores. We also have some small ones for smoothing valve guides after they're reamed. They're claimed to be extremely accurate at smoothing up a bore while enlarging it slightly.

 

[oldskydog]

Muffler expander.