What can I use for sealing threads on an engine/oil

copper crush washer.

nate

Tighten the nipple pipe. It may have vibrated loose.

-- Oren

"If things get any worse, I'll have to ask you to stop helping me."

If so, better to take it out first and use some Permatex or teflon first. Any automotive thread sealant will stand no more heat than is in the oil sump. At that location you could use a hardening type to help ensure you don't unscrew it there when removing the plug for changing oil as it never needs to come out.

Agree. After my post I was thinking of the thread; figuring a non-hardening Permatex - something blue color. Used on other engine parts. They won't leak and you can still get them off easily.

The brand you mention is the solution...imo

-- Oren

"If things get any worse, I'll have to ask you to stop helping me."

Not possible. There is no head to put pressure on the crush washer - it's a pipe.

It's a nipple of pipe, with standard, tapered pipe-threads on both ends, and a threaded cap on the far end. Very common.

With steel pipe and aluminum block, you just give the pipe a bit of a twist with a pipe wrench and move on. Goal: pipe much tighter in block than cap on pipe, with no leakage.

Depending, you might apply some thread sealant, or teflon tape, but you'd have to remove the pipe nipple without making a mess, clean off the threads first, and not let shreds of teflon tape get loose. Which might challenge you.

Later, on draining oil, grab pipe nipple with pliers/wrench while turning pipe cap with another pliers/wrench, so you do not apply torque to nipple.

I guess the sole purpose is to extend the drain for less mess.

I mentioned vibration earlier and to tighten the nipple. Good point of the two metals.

Teflon would be a last resort for me. I would try a pliable, non-hardening sealant, if I really could not stop the leak with a turn or two.

If the nipple can be eliminated...put the plug in the block.

-- Oren

"If things get any worse, I'll have to ask you to stop helping me."