>What did you seal your heater boxes with, if I may ask. I found an old
>pair of boxes at a junkyard for a 78' bus, one is in perfect shape, the
>other has the outer sheet metal shell rusted out in little rings about
>1/4" wide around the pipes coming in from the exaust manifold. I was
>thinking maybe high temp silicone gasket, but didn't know if 700 degree
>max temp rating was good enough, any other suggestions on sealing these
>up?

I seal them by brazing with zn oxy-acetylene torch (not too hot, though!)
and nickle-silver rods.  These rods are pricey, but they have a lower
operating temp, so you don't destroy what's left of the heater box shell.

Thom
-- 
> Immigration is the sincerest form of flattery.
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:    Thom Fitzpatrick                             Transamerica Info Mgmnt  :
:  Systems Administrator                          1860 Howe Ave            :
:  tfitzpatrick@tim.com                           Sacramento, CA 95825     :
:   fax (916) 921-6781                            (916) 565-3346           :
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