All the above. But, before you tear into that
nearly-worst-of-all-Vanagon-jobs, check out the valve. There is an o-ring
under that can leak. Also, when people carelessly put in coolant water
without mixing it, the water can collect in the out-of-the-way heater and
freeze, popping open the housing at the valve.

The valve itself also can leak. There is not much in replacing any of it,
the hard part is getting to it because of the rear seat. You can get hurt
about as badly on that as the transmission falling on you. Be careful.

I do not have a valve or any of that, but I do have the housing, blower and
a good core.

Jim

On Sun, Mar 3, 2013 at 1:51 PM, Finn Runyon <finnrunyon@gmail.com> wrote:

> Our van is nearly ready to hit the road after a year's work to rebuild the
> engine.  I bought this one with a blown engine.  The rear heater os
> leaking, and I am wondering if the valve tends to leak, the O ring, the
> core?  If there is a most common failure I will do that or do generally
> rebuild the whole unit?  The valve defiantly is leaking.
> Thanks,
> Finn Runyon
> 87 Westy Roo
> 89 Westy Pooh
> 12 GTI Autobahn