Camshaft & cam bearings installation problem

[pb]

Hopefully someone can help me out here. I am working on a rebuilt 360. When I got it it was freshly rebuilt to stock specs. I then put in a Comp Cams 260H cam before installing in the Jeep. Ran fine for awhile until my oil pressure started dropping when warm each time I drove it and lost oil pressure to the heads. I pulled the oil pan and found bearing material.

I have been going thru the engine and pulled the cam and cam bearings. Cam looked ok, some wear from the lifters. Lifters appeared to be ok, push rods were clean throughout. Cam bearings were worn and missing some of the top layer(s) of material.

I have a cam bearing installation & removal tool and put in new
Durabond bearings. I have a new Comp 260H cam that I tried to install, but it does not fit. It will get to the oiling groove on the front of the cam and then stop and bind up. I mic'd the cam I took out to the new one and they are the same. Old won't fit either. I thought it might be the brand of bearings so I tried some Clevitte ones and same problem - either cam won't fit.

I've checked each bearing over the cam outside the block and its fine, both sets. I assume they are compressed when put in the block but should still fit. I've checked the bearings to see it they are installed flush/straight in their spots in the engine and they appear to be good.

Is there anything else I should or should not be doing/checking? I need to get this put back together soon before snow and I need a new liver from :razz: TIA

[tufcj]

The cam bearings do compress ever so slightly when fitted into the block. I doubt that you have 2 bad sets.

The only thing I can think of is that your install tool is getting them in slightly crooked (it doesn't take much), or it's creating a burr or ridge just big enough that the cam won't clear (doesn't take much there either).

All I could say is try the cam without the pistons/rods in place, so you can get a clear view of where it's hanging, then measure with a good inside micrometer or bore gauge, and compare to the journal.

Bob
tufcj

[ironman_gq]

had the same problem with mine. mine was hanging up on the rear bearing if you take out the rear plug and look at the bearing you will probably see where the cam is hitting it.

[fifesjeep]

I had an issue with my old 304, the last one was really tight, I nudged it along but I had a burr which was making things 10x more difficult

[AMX69PHATTY]

Just as a side, already kinda suggested, make sure rear freeze plug is not put in too deep into the block. Some cams have a lug on the butt of the cam that sticks out.
:-|

[pb]

Freeze plug is out while it is the stand. I can place the front and rear of the both cams in the f & r bearings just fine when the cam is reversed (put in backwards) if that makes sense. I dont see any burrs with shining a halogen light thru from all angles. Any other ideas before I start pulling them out again?

[fuzz401]

try scraping the bearing ever so slightly were the marks are to free it up did that and put 220 1/4 mile pass on the motor with 70 psi oil pressure at start up and 30 - 40 at when warm