Thanks Brett. I wondered if drilling small holes or at least
scuffing the surface well, would help epoxy adhesion.
I likely won't repair the surface.

WBX coolant pump images from thesamba:
http://images.thesamba.com/vw/gallery/pix/442804.jpg
http://images.thesamba.com/vw/gallery/pix/440570.jpg

@ the list: Did the OEM pump have a dish shaped impeller?
If so, I now see how the previous damage was done.
My new pump doesn't have a dish type impeller that I'm aware of.

On 9/26/14, Brett Ne <brettn777@gmail.com> wrote:
> If I were to use some kind of epoxy to rebuild the missing metal, I would
> drill a number of shallow holes at an angle using a tiny drill bit to give
> the epoxy a good secure bite into the base metal.  In addition, I would mix
> in some fine glass fibers with the epoxy to help keep smaller chunks from
> cracking  apart and flowing through the cooling system.
>
> That said, I don't think that I'd bother messing with it.  I think that the
> only way you'd see any significant loss in cooling capacity is if the
> gouging is continuous from the outer portion of the housing to the inner
> portion, which would allow pressure backflow into the input portion of the
> impeller.
>
>
>
>
> --
> Brett in Portland, OR
> "Albert" '82 VanaFox I4 Riviera
>

--
Neil n

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