96 lt1 rear main should there be a steel ball pressed into one of the holes in the block between the rear main and the lifter valley area?Did the machine shop forget it!!!!!! If so what size is it?Thanks

 

Yeap there is one there in all SBC motors. If you take off the rear main cap and can look down thru the hole where the oil pressure sensor mounts and see thru it, the ball is not there.

Oil Pressure sensor is the hole along the china rail on the back of the block. I'm sure shoebox has a picture of that someplace.

I want to say the ball is 3/8ths, but don't quote me on that. I just take the ball out and put it back in.

Bret

 

Ball is definitely not 3/8. I think it is .473

Whatever it is, it is interference fit with the hole (you tap it in from the rear main cap). Probably .005" over whatever the hole size is.

If my memory is correct, that would make sense since it is .005 over a 15/32 drill.

With the bottom end facing up and standing at the rear of the block it is the hole on the right.

 

I have never seen a ball in there, only a cup plug....and if it's missing the oil will just bypass the filter, it will not cause you to have no oil pressure or blow up the motor immediately.

 

yes it is a .473 dia ball. Thanks (gen 1 small blocks used a plug)

 

Guess they did that to speed up production by 30 seconds per block - never have removed one from a gen II.

 

I have the ball in mine as shown...

EDIT...