With both of the engines I've put together, I used a light coat of RTV on the main cap surface area - the only side of the aluminum retainer that does not have a rubber seal of some sort. I used thread sealer on the retainer bolts. No leaks of any sort in the rear main area on either of these engines.

I don't think any sealer should have to be applied directly to the rear main seal or side seals. The newer side seals are, for lack of a better term, oversized - once installed they will not fall out. The older style used a nail to hold it in place. Make sure the retainer and block are burr free. Clean off any oil before applying the sealer.

I did find it difficult to get the side seals installed. I'm interested in hearing any tricks for this.


Lawrenceville, GA