Oil Drainplug crush washer

Gerbs

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Hi folks
Quick sanity check
Any issue with using a copper crush washer instead of the aluminium. The one I just took off had a rubber o-ring as part of it while the parts fiche just has an alu washer. All I have is copper.

This is what shows in the parts fiche ( https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51556&rnd=10232024 )
07119963252_2_B.jpg
 
If it was aluminium with a rubber inner bonded to it ,it is a Dowty seal commonly used on hydraulic fittings.
I cant see why you cant use a copper washer especially if you anneal it first.
 
If it was aluminium with a rubber inner bonded to it ,it is a Dowty seal commonly used on hydraulic fittings.
I cant see why you cant use a copper washer especially if you anneal it first.
Thanks Mistacat, I've always used copper washers on previous bikes but never know with BMW :rolleyes:
 
Aluminium or copper, they are interchangeable. The idea is that it is a soft material that will deform to create a seal.
I believe that it deoends on the preference of the manufacture. For example, on my Hilux the gearbox and transfer case specify aluminium washers, and the rear axle is copper. The logic appears to be aluminium washer for steel into cast alloy, and copper for steel in steel. However, the front diff is in an alloy casting and Toyota specify copper washers. The front and rear axles are made by different companies.
I fiund the Dowty type washers were more common on Anerican vehicles, did a HD nechanic do your last oil change?
 
Aluminium or copper, they are interchangeable. The idea is that it is a soft material that will deform to create a seal.
I believe that it deoends on the preference of the manufacture. For example, on my Hilux the gearbox and transfer case specify aluminium washers, and the rear axle is copper. The logic appears to be aluminium washer for steel into cast alloy, and copper for steel in steel. However, the front diff is in an alloy casting and Toyota specify copper washers. The front and rear axles are made by different companies.
I fiund the Dowty type washers were more common on Anerican vehicles, did a HD nechanic do your last oil change?
I'm not sure who did the last one tbh, but the copper washer is on there now and no hassles.
Felt like a right fool asking as I've always just used copper on every other bike. Then that Dowty washer threw me off.
 
Thanks for the replies guys. Copper washer is on and is doing what it's supposed to :)
 


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