I have a pretty decent oil leak going on. If I let the car idle in one spot for 15 mins or so then I have a oil spot about 5" big right under where the tranny and engine mount up. Im thinking its either the oil pan gasket (please let it be this) or the rear main seal. Im leaning towards the oil pan since my flywheel is bone dry. If it is my rear main wouldnt I have oil all over the flywheel?

 

When my rear main seal went, I had oil in the bell housing, on the clutch disc, and the rear side of the flywheel.

JamesC

 

Thats good news, I will be changing the oil pan gasket in class Wed and will update then.

 

I got a pretty good deal on a 1969 Chevelle because the owner thought the rear main was leaking. It wasn't. Somebody replaced the oil pressure sending unit and didn't bother to tighten it down. It was leaking like crazy.

 

The dizzy and oil sending unit were the first things I checked out along with the valve cover gaskets. I got the seal today and am putting it in tomorrow. Hopefully I will be posting a happy post tomorrow saying it was the oil pan. I love how I need to raise my engine to get the pan out

 

The great wall across the back is a common culprit as well.

 

I changed the gasket today and found that the rear passenger side 1/2 bolt that holds on my pan is stripped in the block. I put it all back up and its not leaking yet but I will be doing a retap or helicoil on it tomorrow. Atleast it wasnt the rear main.

 

Okay it wasnt the china wall. Im out of ideas. I have replaced seals/gaskets on the following:

Valve cover gaskets

Oil sending unit

Intake

Oil pan

Dizzy gasket



I cant think of anything on the back of the block that can be leaking. If its my heads I would think I would be having more problems then just some oil leaking.

 

Isn't there an O-ring or something on the dizzy?

JamesC

 

Y eah I did that too, thanks..forgot to add it to the list.

 

Sounds like it's time to throughly clean the engine, run it for a short time and then trace the leak.

There may be an additive that glows under a black light that you can add to the oil, (to make it easier to trace the leak) but I've never tried it or even looked for the product.

Good luck!

 

Rear main

 

Turns out it was the oil sending unit. It wasnt leaking from the threads, there was a crack on the bottom of the can itself.

 

Awesome!

Hell of lot easier than a rear main.