H-I-J '76 Nova re-fit.

[HP HUNTER]

Originally Posted by FED 387

Looking at that picture of the bad bearing one side appears to be more worn than the other side that is from left to right do all the others have the same wear pattern???

Yes, I do assume the crank was wet magged?

[Nmbr1GMfan]

Originally Posted by HP HUNTER

Yes, I do assume the crank was wet magged?

It was not.

[FED 387]

Not necessarily in this order but it looks like maybe overfilling (too much oil) causing foaming or aeration --- a blocked oil passage or 2,---- a malfunctioning oil pump or pressure relief valve---- improper bearing selection or installation --- since all the bearings show some damage and those on one side more so than the other side-- also is it possible that you have the left pistons installed on the right bank and vice versa looking at the wear??? and finally crud remaining in the engine block after machining --- You'll find just have to keep on looking FED 387

[HP HUNTER]

Can I see a picture of the crank?

[Nmbr1GMfan]

Originally Posted by HP HUNTER

Can I see a picture of the crank?

This is the only one I have as it was coming apart.

[Nmbr1GMfan]

Originally Posted by FED 387

Not necessarily in this order but it looks like maybe overfilling (too much oil) causing foaming or aeration --- a blocked oil passage or 2,---- a malfunctioning oil pump or pressure relief valve---- improper bearing selection or installation --- since all the bearings show some damage and those on one side more so than the other side-- also is it possible that you have the left pistons installed on the right bank and vice versa looking at the wear??? and finally crud remaining in the engine block after machining --- You'll find just have to keep on looking FED 387

The rods are the last to get oil, they were starved for oil.

[FED 387]

put it back together with new bearings put the CORRECT amount of oil in it fire it up on the dyno then after a few minutes shut it off--- pull the pan see if it has foam--- then turn it over and pop off the rod caps from 5 & 6 see if they look bad --while you are at it may as well check the others too maybe use a "regular" filter instead of that new fancy one you have see if that makes a difference---- might want to check your oil pressure from that small plug front of the engine on top of the block near the timing cover thats the last place that sees oil

[Rich Biebel]

I can't really tell from the picture....can't see the area that would be a parting line if its cast.....

Is it a steel crank or cast ?

A manual trans with a cast crank was never a good idea in my mind.....

Not sayin it cant be done or if that has anything to do with this failure but if I'm letting a clutch out at 5000-6000rpm and maybe on a 2 step I'm a lot happier with a steel crank in there....

I have used cast cranks and had one in my LT-1 stocker.....automatic trans though...…

Dial bore the rod big ends to see if they might be tapered.....Unless they were cut and rehoned that's pretty unlikely.....

Is the thrust OK....? I assume it was....

Looks like most of the trash was soft bearing material fortunately....

[Nmbr1GMfan]

Originally Posted by Rich Biebel

I can't really tell from the picture....can't see the area that would be a parting line if its cast.....

Is it a steel crank or cast ?

A manual trans with a cast crank was never a good idea in my mind.....

Not sayin it cant be done or if that has anything to do with this failure but if I'm letting a clutch out at 5000-6000rpm and maybe on a 2 step I'm a lot happier with a steel crank in there....

I have used cast cranks and had one in my LT-1 stocker.....automatic trans though...…

Dial bore the rod big ends to see if they might be tapered.....Unless they were cut and rehoned that's pretty unlikely.....

Is the thrust OK....? I assume it was....

Looks like most of the trash was soft bearing material fortunately....

Crank is a steel one. Rods were fine when checked before assembly, I will check again. Thrust is fine.

[Nmbr1GMfan]

Originally Posted by FED 387

put it back together with new bearings put the CORRECT amount of oil in it fire it up on the dyno then after a few minutes shut it off--- pull the pan see if it has foam--- then turn it over and pop off the rod caps from 5 & 6 see if they look bad --while you are at it may as well check the others too maybe use a "regular" filter instead of that new fancy one you have see if that makes a difference---- might want to check your oil pressure from that small plug front of the engine on top of the block near the timing cover thats the last place that sees oil

I already know what happened, the volume drop at the end of the line (rods) was the cause. I had no idea the solid lifters would pump so much more oil to the top coupled with the pressure drop from the EDM holes AND the block being machined for cam oiling in the lifter bores just didn't leave enough volume for the rods, my fault. The filter used was a "regular" filter, and yes checking oil at the front of the block would have been more ideal.