Help With Rear Main Seal (On My 3rd)

[Drg racr]

I pulled the motor out of my Ex to re-ring it. It runs good. The problem is, after about 15 minutes of running, it pushed the rear main seal out of the saddle. I've pulled the motor back out, put a new one in, the reinstalled the engine. That one lasted 20 minutes and it leaked. Pulled it back out again, replaced it, put it back together. 15 minutes later, it's leaking again. What am I doing wrong? I've installed it exactly as outlined in the Hayne's manual. The crank is fine, everything is within specs.
Help!!!!

 

[BrooklynBay]

Maybe your flywheel to cranshaft spacer is cracked? Sonnax makes an improved version out of billet steel. The OEM is a powdered iron design which is brittle in comparison. Did you have ATF fluid leaking in that area too?

 

[Drg racr]

I didn't see any flaws when I pulled it. How would that pull the main seal out? The last one I put in went in pretty tight. I can't imagine how that one would push out, but I haven't torn it down again yet.

 

[K.S.MADMAN]

Take a look at this Dead Link Removed

 

[BrooklynBay]

Thanks for posting this link!

 

[BrooklynBay]

Here is some information on the OTC 7786 rear main seal installation tool: http://www.otctools.com/products/detail.php?id=1891