Thanks Alistair. I may have Naval Jelly type stuff lying around my
shop. Have had some success with that product but I bet there's other
products with a higher phosphoric acid content.

I perused MSDS' of various rust converters but didn't see anything
about heat limits other than "flash point".

Neil.

On 7/6/14, Alistair Bell <albell@shaw.ca> wrote:

> I use the blue steel brand tannic acid based latex emulsion type stuff. I
> think it is very similar to plastikote.
>
> Great stuff but it doesn't stand up to heat very well. I doubt it will last
> on the coolant pipes.
>
> I'd wire brush the rust then use a phosphoric acid based rust banger then
> paint.

--
Neil n

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