I have a kinda big oil leak when there is oil pressure and the car is on. Comes out right between motor and trans.
I replaced my rear cover and rear main. I’m in between the oil pan or the oil sending unit. If anyone can give advice that’s would be appreciated

 

Ok I will be Debby downer here.
A car buddy of mine bought low mile 6.0 truck iron block a number of years ago from a local salvage yard to swap into his 71 Nova. The 6.0 had a broken oil pan. He replaced the pan with a 2002 Camaro pan kit. We got the engine/trans in the Nova. Got it fired up and had an oil leak like you describe. So out comes the engine and a new rear cover/oil seal goes in and the engine goes back in and it still leaks.
Come to find out after pulling the engine out the second time and taking it to a machine shop the two long bolts at the back of the oil pan is are very close to oil passages at the back of the block. The oil pan hit cracked the iron block. The salvage yard paid for a new block and bit of labor to reassemble the engine.
Hope this isn't the case. Oil pressure sender should be an easy fix.

 

Are you aligning the rear seal/cover correctly? If the seal isn’t centered on the crank exactly, it will leak.

 

Kind of hard not to algin the new rear cover since it has a "sleeve" to align it over the crank that is removed after install. But stranger things have happened.

 

I toss the alignment thingy. I allow the seal to center itself on the crank flange, while turning the cover until I have equal distance to the pan rails on each side…kinda rock it side to side until it’s even at the pan rails. Then start snugging the cover screws while watching my cover for movement. I NEVER attempt to install the pan until cover bolts…front or rear…are torqued. That’s key.
So what I was getting at in my original question about aligning the cover/seal in post #3 was about how he did the seal. It’s about the same price sometimes to buy a new cover with the seal already in, vs just buying the seal itself. If he changed the entire cover, and tightened the pan bolts before the cover bolts, chances are good that the cover got pulled down and it’s a guaranteed leak. This would 100% fall into the “stranger things have happened” category. Let’s see what Connor has to say…