bugy

i've seen in some engines this has happened... cam bearings went or moved out of its place, why would this happen? then engine just die. would this happen just because of wearing issues? any input thanked in advance.

S10xGN

iTrader: (11)

I've noticed a few threads on cam bearings spinning too. This makes me wonder... Are these all on aluminum blocks? I don't recall seeing any reference to block material, but have never heard of spinning a cam bearing in an iron block...

gectek

iTrader: (2)

I had a 5.3L out of a farm truck that spun 2 cam bearings.

bugy

yeah, it happended on a iron block too, about pour oil level, it was not the point, it was ok, what about cam bearing clearance, do tou guys know something about it?

kballs

iTrader: (1)

A friend of mine has a machine shop and has seen three come through his shop as well.

S10xGN

iTrader: (11)

Any of them completely stock? Maybe it could be narrowed down to stock vs. aftermarket-parts...

Pumba

If you talk to Sean at ERL Performance he will tell you that they regularly pin the cam bearings in aluminum blocks. This is because the aluminum expands more than an iron block.

For a high performance engine, it is a good practice to pin the cam bearings.

-

racer7088

Never seen it even on road race cars ever when people that knew what they were doing were building it. Seen it often on cam swaps or with new cam bearings and people didn't check the cam for binding or bearing clearance or for a bent cam shaft. Many cam bearings are thicker than oem and many cams are larger by .001-.002 on the journals and then the cam maybe slightly bent in shipping as well. Also all the oil gets wiped off by the time the cam is all the way installed in the back cam bearings so I put oil on the bearings and the cam when installing.

Check the cam for straightness.

Check the cam journals for correct size.

Check your cam bearing clearance to the installed cam bearings.

Have cam straightened and/or have journals reduced to 2.165 OEM size.

Make sure cam bearings are installed correctly and oil can get to them.

= NO problems

bugy

yeah, it seems to be the right steps to work without concerns, about to pin bearings, it sounds kind of something good to try, but it depens on machine shop people if they are able to do it... thanks for advicing guys