Hivelocit

iTrader: (7)

Anyone have trouble sliding their cam into place?

I have a used 2004 LQ4 that I had taken to the machine shop 2 years ago. Purchased Clevite Cam Bearings SH2125S and had them installed. Re-using the stock cam and cannot for the life of me get it to fit properly. Got the first journal in but it was a tight squeeze and felt like it was binding a bit and cannot get the second journal through. There is noticeable marring of the bearings as I proceed so I am thinking the bearings are too tight. Anyone else have this issue I do not remember ordering anything else but stock bearings so WTF! Used a micrometer on the cam journals and I find them within spec 2.16 and the ID of the bearings measure extremely close at 2.167; albeit there could be a margin of error here on either end since these measurement tools are harbor freight specials. Any suggestions? Guess I will be going back to the machine shop on Monday....

Hivelocit

iTrader: (7)

I am sure it is buried deep somewhere, but what is the standard cam bearing clearance? All of my searches have produced moot!

Jake75

iTrader: (2)

had this happen to me with some clevite coated bearings on my 408. I replaced the bearings with some non coated bearings and everything was fine.

Hivelocit

iTrader: (7)

That's the strange part, these are not coated and the cam is in between specs so it is wore down a little. Anyone ever used 600-1000 grit sand paper? I can see that probably being a bad idea...

Wolftrk99

iTrader: (5)

Yes it would be a bad idea, did the bearings get damaged when they were installed, had that happen to me last year, rebuilding a 6.0, ended up having to replace 2 bearings because they got slightly damaged on the leading edge being installed http://www.pleasurecraft.com/manuals/L510016.pdf this may help with specs..

Hivelocit

iTrader: (7)

Im starting to think I purchased the wrong bearrings. In mid 2004 GM updated the lq4 and a few internals changed; one of them being the cam bearing joirnals.

Wolftrk99

iTrader: (5)

The machine shop that installed them should have caught it, the cam journals on the cam itself should be the same for all the ls style engines.. otherwise youd have to use a specific cam and for example wouldnt be able to use a 3 bolt cam in the gen iv engines

Wolftrk99

iTrader: (5)

According to summits application guide the change was in late 03 blocks if your block is an 04 those should be the correct bearings.

Lundy

I work at a small automotive machine shop and we found you have to be very careful with the front journal. A lot of the time when installed the bearing gets started crooked and it misshapes the bearing making it a tight fit(cam won't spin) or the cam will not go in at all.

Hivelocit

iTrader: (7)

Seems things rolled out slowly. My engine is a 2004 LQ4 but it has the older style rods (non LS2) but the pistons do posses the Teflon skirting. Also my head bolts are from the earlier design (different lengths). I have been reading around the internet and someone said that my block (GM 12551364 ) had the earlier Cam journal dimensions. Who knows, I will bring the block down with the cam and two different bearing sets and see which fits. Could also be the fitment of the bearings previously like stated above. I will post back this week with the details. Thanks everyone.