Tip of the day

So a while back I bought a brand new Milodon road race oil pan, installed it and put the motor on a dolly while I work on the car. I put oil in it to prime the motor every now and then. Well one day I noticed a small puddle of oil and it was clearly coming from around the drain plug.. So I cleaned it up and tightened the plug - which was already pretty damn tight! Well that didn't solve the problem so now I'm worried that there's a pinhole in the welded bung. So I put the motor back on the engine stand ready to pull the pan if necessary. I drained the oil and cleaned everything off and saw that the plug "gasket" is actually a copper washer - and a pretty hard one at that! So I figured I'd cover all bases before pulling the pan and went and bought an assortment of drain plug washers. The first one I tried is a steel washer with a rubber or viton seal molded onto it. I filled the oil back up and it hasn't leaked a drop in a week (the original would form a drip in a couple hours). So MY lesson is to keep spare seals on hand and use a new one with every oil change. Its worth a buck not to have oil dripping and have to drain seven quarts to fix it. Now I'm keeping my fingers crossed that the rear crank seal doesn't leak when I finally fire the motor !!

Those are a real pain.

Yeah, the ones with the rubber/Viton in the ID area are the best, I use 'em on the pan drain plugs. I hate leaks.
In a pinch, nylon or soft copper is good.
Never understood the use of hard washers for that purpose, except maybe to keep the wrench from scratching the pan...

ive always used nylon ,never a leak from that area.

I had a job to change the oil pump so I drained the oil then put the drain plug back in the hole finger tight.

Dropped the pan. Serviced the oil pump. Reinstalled the pan and drove the car. Peek under to see if oil may be leaking from oil pan gasket, all good.

Next oil change interval I grab the wrenches, crawl under to find. This oil drain plug is only finger tight and has not lost a drop of oil.

From that day on I realized, that rubber impregnated plugs are the best and they do not need to be overtightened.


Glad you fixed your Milodon pan leak.

I bought a new oil pan bolt from NAPA and it was undersized just enough that it would not seal. I ended up putting a small wrap of plumbers tape right under the head of bolt to seal the last few threads along with a rubber gasket from the hardware store that I replace every time I change the oil. The tape works in a pinch, but you don't want it getting inside the oil pan so make sure it all comes out with the bolt. I should have probably went to the wrecking yard and grabbed an oem bolt off something else and it would have fixed it.

I've found that several cycles of tightening, loosening and re-tightening bolts that require either copper of dead soft aluminum lead to the bolt to turn in a bit farther than it would with just one cinching up of the bolt. The process has fixed leaks and banjo fittings on my carbs, oil pan leaks and brake caliper banjo fittings.

I assume it is because the washers are a bit hard and cycling them tight and loose a few times allows the crush washer to seat better between the parts.