Cam bearing replacement with rotating assembly installed?

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Mar 25, 2015 | 07:37 AM

welder350fd

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From: MA

Cam bearing replacement with rotating assembly installed?

I picked up this '03 LQ4 for my '97 k2500 suburban ls swap. Unknown mileage on the engine, It had blown head gaskets. Internals of the engine look ok, no sludge build up. I am trying to leave the rotating assembly stock (for now) and in the block. I am putting a Cam in and better lifters, HD timing chain, Melling HP oil pump. That is about all I am going to do with the short block. I pulled the cam and the bearing surfaces on the cam look ok but the bearings dont look so good. looks like a lot of deposits or something. I am new to the internals on an LS engine so any help would be great. Do these bearings look as bad as I think they are (need replacement?) and if so, is it possible to replace the bearings with the rotating assembly still in the block? Thanks.

This is the Cam bearing at the back of the block

one of the bearings in the middle of the block

bearing at the front of the block

Mar 25, 2015 | 08:03 AM

WE TODD DID

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Looks like oil tarnish. I bet they're okay. But to answer your question, yes you can replace them with the rotating assembly installed.

Mar 25, 2015 | 12:24 PM

welder350fd

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The bearings don't seem to have any gouging in them, they just look very very dirty. I wouldn't expect to see that much buildup on a cam bearing.

Mar 25, 2015 | 12:38 PM

welder350fd

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I am just wondering since i have it down to the sort block if its worth changing these out (myself or a shop)

Apr 2, 2015 | 03:20 PM

Vito.a

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I'd first want to put a straight edge on the decks (both block and heads) to see why the head gaskets blew.
If the block needs decking, then you have to take it apart anyway.

Then, what is your goal for this motor. How long do you want it to live? From the looks of it, it has had a pretty long service life already (looks like it was run hot). How are the cylinders (crosshatch)? Any ridge at the top?

It may be easier and less expensive to rebuild it now than after it tosses a rod out the side.

Apr 2, 2015 | 03:35 PM

welder350fd

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Right now Its getting swapped into a '97 K2500 Suburban. I am getting new 317 heads and porting them. LS6 Springs, and a cam. that is about it. Hoping to run this as a DD for the next 2-3 years. basically just want to pull of a successful swap for now. Then its getting pulled out and a bored and built lq4 will be going in with a some boost.