Cam bearing installation

Hey everybody,

Don't know if this will help anyone but had a little trial and error installing cam bearings today. I don't have the correct J tool specified in the manuals, so that may have been part of the reason I had trouble, but I had good luck doing it this way with my Lisle cam bearing tool...

In the military manual, as well as the GM unit repair manual, it says to install the outer camshaft bearings #1 and #5 first. "These bearings serve as guides for the pilot, and help center the inner bearings during the installation
process." Then follow by installing #s 2 and 3 through the front of the engine, using the front bearing bore as a guide, and # 4 through the back of the block using the rear bore as a guide.

The problem I ran into with this method (at least on my block) was that the cam bearing bores are all chamfered from the front side, not the rear. When I installed my first set, the two rear-most bearings 4 and 5 ended up galling on their way in and transferred to the ID of the new bearings, causing a tight fit of the cam. What I ended up doing was using a short handle bearing driver to install the #1 bearing (make sure it's square going in) and then install 5-2 with the cam bearing tool through the front of the block starting with the rear bearing in descending order. I'll add that I also stuck the new bearings in a freezer the night before to make them go in easier. Could probably just install 5-1 all through the front, like most engines, but I figured I'd try to at least use the front bearing as a guide as they outlined in the manuals. Worked for me at least, and now the cam spins by hand with no binding whatsoever.

Not sure if this will help, but maybe will save the guy or gal down the line from eating a set of bearings like I just did. Or even better, just have the machine shop do it like I should have done while they were boring the block. :rolleyes:

Cheers!

Hi Alan,

The #1 and #5 cam bearings, like your mentioned, need to be installed first to provide stability for the installation tool - so the 2-3-4 bearings can be started straight.

As long as that is done, I would install the inner 3 inner bearings using the chamfered side of the cam bearing bore as the entry side. In addition, you could use a little 200 grit wet/dry paper to smooth any burrs on the edge of the bore entry side.

Make sure the oil hole in each bearing is correctly clocked. When it says to position the oil hole at 11:00 o'clock (for example), that assumes the block is sitting upright and you're facing the front of the block. If the block is upside down, which is where it'll sit when installing bearings, you'll need to account for that. Having the oil hole in the incorrect position could cause bearing failure.

Jim

Thank you for your reply, sorry for the late response, I'm just now seeing this. Always appreciate the advice! This place is a gold mine of information. Looking forward to getting my 6.2 book in the mail. It was good talking to you today!