Are rear main seals interchangeable between LA and Big Blocks?
With a little digging, I found out the following.....
The rear seal surface on the 440 is approximately 2.81 as shown on these Chinese digital calipers......
A 318 crank I had was smaller.....
Here was a weird discovery....the final one was a 360.
Whuuut?
My situation could be the following:
* Correct 440 seal in right but not sealing well.
* Correct 440 seal in wrong, the half in block is in right, the half in the retainer is in backwards.
* Incorrect 318 seal too small, leaving a gap for oil to leak out.
* Incorrect 360 seal too big, distorted when the retainer was tightened down, leaving gaps for oil to leak out.
Oddly, the 360 crank main journal is stepped up in size at the oil seal area. Why???
I really need to keep my gaskets separate!
With a little digging, I found out the following.....
The rear seal surface on the 440 is approximately 2.81 as shown on these Chinese digital calipers......
A 318 crank I had was smaller.....
Here was a weird discovery....the final one was a 360.
Whuuut?
My situation could be the following:
* Correct 440 seal in right but not sealing well.
* Correct 440 seal in wrong, the half in block is in right, the half in the retainer is in backwards.
* Incorrect 318 seal too small, leaving a gap for oil to leak out.
* Incorrect 360 seal too big, distorted when the retainer was tightened down, leaving gaps for oil to leak out.
Oddly, the 360 crank main journal is stepped up in size at the oil seal area. Why???
I really need to keep my gaskets separate!