Re E36 Yellow gunk inside oil cap

[Jim Cash <j.cash@xxxxxxxxxxxx>]

Len

Other writers are correct - you are not driving enough in the cold
weather to heat up your engine and get the previous condensation burned
out of it.

You are geeting enough water condensing in there to mix with the oil.
the moisture condenses on the underside of the valve cover and mixes
with oil film there - that is the yellow gunk you see.

As well as water you are also getting acids, etc building up quickly,
and while you can't see them they are doing worse damage.

As well as making at least one good hot trip a week it is also wise to
change your oil frequently in those conditions.

I had those short driving conditions for a few winters, and changed my
oil every month - even with only about 500 kms between changes.


Cheers

Jim Cash
London, Ontario, Canada

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