Oil drain plug crush washers

[brianl703]

I changed the oil on my friend's 1997 Del Sol. I bought a crush washer for it along with the filter and Mobil Clean 7500.

I handed him the crush washer and told him not to lose it. I removed the oil drain plug (which required using a 1 foot ratchet..which should've been my clue that something was wrong..) and I couldn't get the crush washer off of it.

Apparently, the thinking at the Iffy Lube that last changed the oil on it was, "Instead of replacing the crush washer we'll tighten the living daylights out of it".

So we had to go to Autozone to get a new drain plug, and in the process he misplaced the new crush washer..and Autozone didn't have any.

So I just got a new drain plug and a rubber/metal gasket and put it on and it seemed to work fine. (They were out of the Motormite drain plug their computer listed for the Del Sol, but the box listed the actual thread size and they did have a drain plug of another brand in that size, so I got that instead).

So I ask, why crush washers? What benefit do they offer over a rubber/metal gasket? Why wouldn't someone want to use a rubber/metal gasket instead of a crush washer?

 

[Mickey_M]

quote:

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brianl703:
..... So I just got a new drain plug and a rubber/metal gasket and put it on and it seemed to work fine. (They were out of the Motormite drain plug their computer listed for the Del Sol, but the box listed the actual thread size and they did have a drain plug of another brand in that size, so I got that instead).

So I ask, why crush washers? What benefit do they offer over a rubber/metal gasket? Why wouldn't someone want to use a rubber/metal gasket instead of a crush washer?

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New crusher washers make it easy to get the torque right without a torque wrench and without overtightening the plug.

They also conform to irregularities, and so you get a nice seal.

For similar reasons some spark plugs use copper crusher washers and they need to be replaced each time the plug is removed. (On the plugs they also have superior conductivity of heat)

I keep 100 or so each of the drain plug sizes I use in fiber and in nylon. They're used one time, again so that I can tighten them by feel and not risk overtightening.

Between the fiber, the nylon, and the copper crusher I've never seen a difference in sealing.


.

 

[brianl703]

I suppose then that the main advantage a crush washer has over the rubber/metal washer that I used is that the crush washer provides feedback when the correct torque is reached.

Otherwise, a rubber/metal washer should seal as well as a crush washer, and is reusable unlike a crush washer.

 

[ChrisW]

The rubber can detoriorate over time constantly reusing it and all, figure heat and oil. I've seen it happen to just about every car of my friend's that I service once in a while. The rubber begins to seperate from the metal ring that holds it in place.

I use new cruch washers because they are cheap insurance. They are what, less than $.10 ea?

Hondas use aluminum, Audi/VW use copper, toyota uses some type of metal with a very thin fiber on one face; I'm not sure what others use. I carry supplies for honda, vw, and toyota.

 

[brianl703]

It may, I have no long-term experience with any sort of separate drain plug gasket. All of my cars have drain plugs with a built-in rubber gasket. My mom's old 1997 Ford Escort was recently sold at 88,000 with the original drain plug still in it, which is of that type.

I would expect a metal/rubber gasket to last for at least a few oil changes, which is a few more oil changes than a crush washer is expected to last.

Although crush washers are cheap, they are just another thing to keep track of between oil changes.

 

[srivett]

My brothers oil pan warped on his VW and he lost 1 litre of oil over a month! This was with the car parked for a month straight in sub freezing temperatures. He had to remove the copper gasket and get a fibre gasket to stop the leak. Replacing the plug and copper washer didn't help.

Steve

 

[Cyprs]

My QR25DE requires copper crush washers, my service manager told me to change crush washer every every 3 OCIs, I go at times 5 OCIs on one washer, never had a leak, my torque spec is 22-29 foot pounds, I do 30 ft lbs on these Nissan crush washers using them 3-5 times for years now with no leaks.

Cyprs

 

[ChrisW]

I would never reuse a crush washer if I could help it. The reason its called a crush washer is because it crushes when used. I suppose you could anneal it.

Also, reusing the crush washer can throw off the torque, I assume that the torque spec is figured with how much the washer will crush using that spec.

 

[Cycle Freak]

I have owned GM's for the last little while and they have a soft plastic like washer on the drain plug which if you tighten the plug to the right torque spec. seems to last for the life of the vehicle. I do own motorcycles and in the manuals they recommend changing the soft metal crush washers on the drain plug EVERY time you change oil which I just started doing a few years ago after having some leaks when I didn't change washers that looked like they were a permanent part of the drain plug from being re-used, the honda dealer laughed when I told him I didn't realize that was supposed to be changed each time and he said for .30 cents each it was cheap insurance to make sure you got a good seal on your drain plug.

 

[moribundman]

My car uses a crush washer on the drain plug. The washer develops a ridge when properly torqued and cannot be reused. Well it can...

 

[Al]

Nissan uses crushed washers for at least 25 years. I had a B210 and maybe replaced the crushed washer 2 or 3 times in proably 40 oil changes-with nbo problems. My 01 Sentra gets a new washer every couple of changes if its lucky. Don't sweat reusing them.

 

[Cyprs]

Al, a B210, that brings back memories, I bought a 1977 F10 new in 1978, it was a demo. Did your Datsun/Nissan have the 1400CC too? Great engine.

You know, I was just a late teen kid then, I changed my own oil and never changed a washer, if it had a crush washer it was pressed on and I didn't know there was supposed to be a washer. I took drain plug off and put back on as I found it for years of changing oil, never had a leak.

Your post made me realize I too went years of changing oil with one crush washer on my F10 Datsun. Great cars Nissan/Datsun then and now.

Cyprs

 

[blupupher]

I have never replaced the crush washer on any of my cars till I got my Elantra. The dealer gives you a washer when you get a filter, so I did replace it. On my Elantra I now have a Futmo valve, so it is not an issue, on the Tucson, I am changing is every 2-3 oil changes.

 

[Cyprs]

Thanks Al, Nissan engines were "keep it simple stupid" in those days on Datsun F10 and B210s, no overdone worrysome high tech then, less power but more reliability. (Still faithfully drive Nissan though)
Cyprs

 

[Al]

quote:

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Originally posted by Cyprs:
Al, a B210, that brings back memories, I bought a 1977 F10 new in 1978, it was a demo. Did your Datsun/Nissan have the 1400CC too? Great engine.

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I am almost positive it had a 1200 cc engine. And this was a great engine. It did take a head gasket but When I got rid of it with around 120K miles on it it used no oil (that you could notice) and the oil stayed very clean. Probably indicating that the rings sealed very well.