2002_Z28_Six_Speed

iTrader: (19)

I had a motor built recently and it blew up. I am trying to prove that bad QC from the builder caused the failure.

My stock bearing was not clocked in this position. Both holes were down. On the tear down of my blown up motor I found the cam bearing in this position? Is this an issue???

The builder put one oil hole in the 11 o clock position and the other at 3.
My stock bearing had oil holes at 5 and 7 o clock.



Does it matter?

07NBSChevy

iTrader: (1)

I know when I had a shop install cam bearings they had to be lined up with the holes in the block. I think they were at the locations you mentioned, 5 and 7 o clock.

This thread discussed how they need to be lined up.
https://ls1tech.com/forums/generatio...ientation.html

Not my picture, but this is how they had to line up in my block.

jimmyp3353

iTrader: (3)

Oil passage is at the 3 oclock location, the other hole in the bearing isn't used if I'm not mistaken.

2002_Z28_Six_Speed

iTrader: (19)

here is my stock motor. completely different.

A.R. Shale Targa

iTrader: (2)

What was the terminal illness ???
Cuz starving the cam journal will only chew that particular journal up and might run a bit longer than expected.
Usually premature engine failures are related to bearing clearances in the lower end.
I've personally seen factory rods re-torqued with the original bolts and the big end was distorted by a full thousandth of an inch which needed resizing.

s57_s2k

you only have to locate one of the holes on the oil gallery , it does not matter where the other hole is located .

jimmyp3353

iTrader: (3)

As long as the hole is in the 3oclock position it doesn't matter where the other hole is.

KCS

iTrader: (20)

The oil passage in the cam tunnel is at the 3 o'clock position but it's about an inch long so the oil hole in the heading cam be installed between say 2 to 4 o'clock and be okay. You can check with a light and inspection mirror, or use a small Allen wrench and stick it in the cam bearing oil hole to see if it goes into the oil passage in the block.

2002_Z28_Six_Speed

iTrader: (19)

I appreciate the advice. I know it sounds easy to a vet engine builder but it saved me a lot of timing knowing it was OK. As compared to me ripping the engine out and having to buy and wait on the tool to remove the bearing.

Thank you!