afterrun coolant pump

Brett Dikeman brett.dikeman at
Fri Oct 2 20:00:20 PDT 2009

On Fri, Oct 2, 2009 at 10:52 PM, Bernie Benz <b.benz at> wrote:

> Most oxides of iron are non magnetic
>. Magnets are an old Audi wife’s tale!

Really.  So what do you think was all the stuff stuck (magnetically)
to the pump impeller that I took apart after it failed with 150K on
it?  Fruit loops?

> Can’t hurt much, but the wallet. Detergents are only useful if there is oil
> in the cooling system.

A small amount of oil makes its way into most car cooling systems over
the course of years.

>Better, use oxalic acid, the active
> ingredient in commercial radiator flushes, available cheap in full
> crystalline strength from your local paint store, ask for wood bleach.

Citric acid is what used to be in the flushes.  Companies switched to
oxalic, probably because it was a little cheaper.

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