Oil Leak At Hand Hole.

[Justin Morgan]

Trying to put my dad's TO-20 back together after replacing the oil tube that holds the oil filter assembly together. I can not get the plate to seal back up onto the oil pan without leaking. I've put a new rubber o-ring/gasket between the plate and the pan and still get a slow drip. The Operation and Maintenance book says, "To prevent leaks due to gasket stretching, firmly shellac filter cover gasket to pan or gasket cover."

How do you "shellac" a gasket to the pan or gasket cover?
 

[John(UK)]

Shellac is a varnish-like "paint" that you apply and this makes the seal...John(UK)
 

[Justin Morgan]

I tried "Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker" along with the rubber gasket and it still leaked. Does the Shellac work differently from the RTV?
 

[Todd Broucksou - MCNC]

I used the ultra-black silicone, had to do it twice, and it worked. Also used new copper washers on the the two bolts (drain and filter plate).
 

[Bruce(OR)]

Make sure the tube is screwed all the way into the block.
 

[2tractors]

That plate seems to get bumped around and deformed, coat both sides of the rubber gasket filling in all the low spots and tighten.Leave it overnite before adding oil.
 

[ShadetreeRet]

Hmmm, hadn't heard the term "gasket shellac" for quite sometime now. It has been pretty well replaced with gasket maker in a tube which generally works better anyway. When those tractors were built, "shellac" was about the only sealer available. It came in a can with a brush applicator made onto the cap, and before you installed the gasket, which was generally cork back then, you painted both sides with shellac. Darned stuff worked too, 'cause when you removed a gasket it required a lot of scraping to get the old stuff cleaned off.