Is a rubber plug sufficient to stop an oil leak?

Dear Car Talk

Dear Car Talk | Oct 01, 1995

Dear Tom and Ray:

I'm writing for my daughter, who is a single parent with two kids and little income. The oil pan on her 1986 Nova with 60,000 miles has been stripped. We installed a self-tapping replacement drain plug, but after a while, that leaked, too. We are now using a rubber plug which we replace after each 3,000 miles oil change. But we are afraid of this plug leaking or coming out while driving. How safe are they? The cost of replacing the whole oil pan at the dealer is $185, which my daughter can hardly afford. Urgently need your expertise. Please help.

RAY: What you're doing is just fine, Charlie. That rubber plug isn't going anywhere.

TOM: For those of you who aren't familiar with these things, the rubber plug in it's natural state, is "bulged" out. You use a special tool to stretch it and make it thinner. And in that stretched position, it's thin enough to fit into the oil drain. Once you get it inside, you remove the special tool, and the plug bulges out again inside the oil pan and stays put.

RAY: And I wouldn't worry about it popping out. Once you release the special tool, that plug is really wedged in there. It's in there tighter than my brother's underpants after the school bullies gave him an atomic wedgie (for those of you unfamiliar with the terminology, that's when the final position of the elastic waste band is actually stretched over the forehead of the wearer). Seriously, if that rubber plug is installed correctly, I don't think anything is going to force it out while you're driving.

TOM: I would be careful about reusing it, though. They say you can use them several times, but I wouldn't. I'd do what you're doing and replace the plug every time you change the oil. Good luck to you and your daughter, Charlie.

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