Originally Posted by Uncle G.

I once had an intermittent leak from the front lower pushrod seal that drove me nuts. It turned out that the front exhaust pushrod was slightly bent-not actually "bent", but the threaded section of the adjustable pushrod was brazed to the shaft a bit crooked. Every so often, as it rotated, it would rub on the pushrod tube, and once in a while would "rock" the pushrod tube enough to break the seal at the lower o-ring, causing a leak that came and went.

Not saying that is your problem, but it's something to check for. It's most likely to occur on the front exhaust position, since that pushrod operates at the greatest angle.

Originally Posted by jammerx

Don't use synthetic unless you have new gaskets. Just run HD Dino...