Leaky Aluminum Drain Plug Gasket

Aug 16, 2019
I decided to do an OCI yesterday and was going to re-use the gasket that has rubber in the middle and metal on the outsides but I misplaced it after I took it off, then found it later. So I put an aluminum gasket on it, and it leaked, so I removed it today and put a plastic one on and it no longer leaks. The plastic one didn't take as much torque to tighten the bolt as the aluminum one, which still leaked. Why did that aluminum gasket leak? I was afraid to tighten it any more, afraid I'd strip the threads on the bolt and that's why I instead replaced it with a plastic one.

Is it OK to re-use drain bolt gaskets?
I seem to have reused them many times in the past and it doesn't seem like any of them every leaked.
I would love to see pics of the faulty drain plug warsher.
There have been literally hundreds of millions of reused warshers with no issue.
I use about 25 pound feet of torque on the drain plug.

Of course, if any drain plug gasket is beat up, throw it in the garbage.
One thing you could consider is installing a Fumoto drain valve. If you don't like that idea, I would get a new drain plug.
I went to a Toyota dealer to buy crush washers for my wifes new Corolla Hybrid. The parts counter guy gave me a few at no charge.
The OEM Toyota crush gasket has a blue teflon coating on both sides.
I don't re-use them. Ever.

When a new genuine Toyota washer (plastic coated aluminum) costs .25, and an aluminum washer costs less than .05, why re-use them? I get new washers in bulk, or ask the parts person for one when I get the filter. New every time and never a leak.
The aluminum washer is designed to crush in order to take the stress off the threads. You will actually feel it compress as you're tightening. I believe it was @Chris142 that mentioned, it's similar to a spark plug gasket, which is an excellent comparison, in a recent thread about crush washers. I replace them everytime.
The leaky one is on the right. I have other aluminum ones like it that look in better shape than this one. This one has imperfections for some reason.

I was running the one with rubber in the middle which did not leak.

I also have a feeling the copper one and the other plastic ones would work fine.
The plastic one I used is wider and thinner than the two plastic ones pictured on the left.
It seems to me that I've always done well with plastic drain plug gaskets.
I've got about a dozen of these gaskets and I think they'd all fit my Prius drain plug bolt.
It doesn't seem like I'll be needing to buy new ones for a long time.

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On Toyotas and Nissans, I use a 12mm copper and 14mm aluminum ones for Hondas and other makes. Just make sure you crush it enough to make a seal; I go by feel. I avoid the fibre or plastic ones but will use them in a pinch, pun intended.
I understand that these gaskets are very inexpensive, but if they can be reused several times with no leaking at all, why bother using a new one every time? If I notice a leak with any of them, it's easy to just take off the bolt and put on another gasket.
I saved the leaked NAPA FS oil to a clean pan and put it back in the engine.
I probably would have been fine with the aluminum washer if I had "crushed" it on.
That said, I think I'd rather use plastic ones that take less torque to get a good seal.

I don't have a torque wrench any more. Should I get one just for this?
In order to protect your threads, replace them everytime, just snug it up and it will be fine; don't go overboard. My opinion is that the new washer also acts as a retainer of sorts, the gasket performs so many tasks, they're worth every penny in my experience on so many levels. A torque wrench is unnecessary, you'll get the feel for it after you do it a few more times.
If the drain plug washer hasn''t developed a ridge or has not been deformd unevenly during the initial tightening you can safely flip it and reuse it. I'd rather not use the same water a third time. A new 30 cent washer should fit in the budget.
That warsher is a goner. As others have said, buy in bulk and have them on hand.
I keep Honda/Acura, Toyota and Nissan, plus assorted others.
When in doubt, toss it. Or just use a new one every time as @Astro14 and others have said.
I like torque wrenches mainly because I hate over-torqued drain plugs. Nothing good comes of that.
Also, if the drain plug does not thread in easily by hand, find the problem and toss it if in question.

Good luck.
I like torque wrenches mainly because I hate over-torqued drain plugs. Nothing good comes of that.
I know what you mean. The 2016 Ford Fiesta I bought a couple years ago had the drain plug on so tight that I could not budge it and had to take it to a car care place to get them to loosen it so I could change the oil and filter. I was sitting in the car when he loosened it and it rocked the whole car back and forth. I don't know who in the world would want to tighten a drain plug up that tight. That's insane. The lady worked at a car care place and evidently the mechanics over tighten things when the cars are on an elevated lift where they can get a lot of leverage while standing under the car.
I've never replaced a drain bolt or washer. Maybe because the bolt has a washer built in with a rubber washer. They look like this >>>>>