dbrick wrote:The leaks I see the most are the distributor area or the oil passage at the back of the head, it runs down and back and looks like a rear main. Clean it all and recheck to be sure. If it's still a small leak, I'd tolerate the free rust preventative and park on cardboard.
If you're not sure, clean well and spray with spray foot powder. Any leaks leave a track in the powder residue. Cleans off easilly
If it is the rear main, here's food for thought, seems like a great logical fix, and a whole lot easier than pulling the engine.
From a muscle car site, but applies.
The Pontiac factory service bulletin detailed the following fix. I've done it a few times now and it works better than the other methods.
1) Pull the pan and remove the rear main cap only.
2) take a soft brass drift and bump the ends of the seal that remains in the block back up into the block about 3/16 of an inch. This will swell the seal in the block and make it seal tight again.
3) Remove the old seal from the cap and roll in the new seal. When you trim it, use a fresh razor blade and cut the seal about1/4" over long on each side. Use a fresh blade for each cut to make it nice and neat.
4) apply some RTV to each of the cut ends and the parting line. feed the ends into the spaces in the block and torque the cap down.
5) reassembly is reverse of disassembly.
dbrick,
Great Idea here! Have some questions ...
A.) Can the main cap only work? Guess it can be removed without removing oil pump (suspect I need to order pump gasket just in case)?
B.) Any particular RTV for this job?
C.) And the parting line (referring to the purple colored text above) is what? Is this the area between the seal and the bearing cap metal?
My leak is a humble circle the size of a half dollar seems to drip right beneath the plate on the transmission.
Seems likely to be the rear main seal. But I can live with it for now ... gathering info though just in case I wake up at night
and want to work on the Datsun!