Brass or Copper Crush Washers

[Kroosa]

I have a technical question. I have easy access to copper and brass washers, both of which are commonly used as crush or seal washers in heavy equipment maintenance. I do not have easy access to aluminum crush washers, that is to say the ones called out for use on old Wings. Is there any reason why one could not just substitute a copper or brass crush washer for an aluminum one when installing a new water pump? I know copper crush washers are available for use on the brake line fittings. Electrolysis issues occurred to me but I am not smart enough to figure out electrolysis in an engine environment with heat, oil and coolant all mixing about.

Anyone know the answer? If not, anyone have an opinion? Ha, that should get a response!

[CYBORG]

never thought much about it. if you have the proper size copper, i would consider them over the brass

[Roady]

You should get a set of the 3 alum. washers with either the pump or seal kit (not sure which one). I would just use those.

As you thought ... there might be a problem with dissimilar metals.

[robin1731]

snip............

As you thought ... there might be a problem with dissimilar metals.

Maybe but we use copper washers on the brake lines. With aluminum bodies and steel banjo's. And you are using steel bolts to hold the aluminum water pump on. The only thing I wouldn't be sure about is the copper washer in the coolant. Like Cyborg I would choose copper over the brass. Copper is a bit softer and it is after all being used as a crush washer with a bolt that is only torques to 8-9ft-lbs.

[scootsx2]

When I replaced the brake lines on my sidecar outfit this past winter, I found copper crush washers had been used with the old lines. The new lines came with aluminum crush washers.

[Kroosa]

Hmmm. Having trouble now locating the correct size in copper. Lotsa brass. If I have no joy in copper I will just order the aluminum ones from Partzilla, they sell them separately. I need to make a parts order anyway and can easily justify an add on. This is simply not something that I want to take chances with.