COPPER O-RING
 

1991 420 SEL
Anybody know where the copper O-Ring goes that comes with the oil filter? I'm guessing it goes between the canister mounting assembly and the engine block. I've never had it off. Shoud it be removed and cleaned every so often?:confused:
Thanks for any help.

On the drain plug. 14mm dia.

The larger copper washer is for the R107 (SL).

Too big in diameter for the drain plug. Approx. 1" ID. It's round in cross section. Not flat like a "crush" washer. The filters come with an Aluminium "crush" washer that goes under the head of the canister lid bolt.

I'm thinking it may be a seal between the canister assembly and the engine block. I've never had this off. Do you know if it should be removed periodicly for cleaning. It's no big deal for me as I have a lift and a full shop.

Thanks for your help.
Dave

Copper, brass and bronze alloys are non-ferrous metals with excellent electrical and thermal conductivity as well as good corrosion resistance, ductility and strength. Pure copper (Cu) is an unalloyed metallic element. Low alloy copper contains very small amounts of alloying elements such as aluminum and titanium.

Copper O-Ring
 

Thank you Professor Layton for very valuable and concise treatise on metallurgy. However, the chemical composition of non-ferrous alloys is secondary to my inquiry.
The physical placement of the subject component was my primary interest.

Well, yeah, but you never know when there might be a pop quiz on this stuff.