Well the first and most obvious thing is heater boxes in good shape. The
bus more seem more intelligently designed than the bug versions, with decent
clamps and insulated pipes. We completely disassembled the whole system and
replaced all the rubber (those orange valve flap/discs break down and
become brittle under all that heat); then cleaned everything and made sure
all the clamps worked properly. Then I used permatex; bronze or black is
ok (still hasn't broken down or come off) on all the joint facings and any
small holes. Other than welding which sounds like a good idea but more
permanent there isn't much you can do except to make sure your heater flap
controls work properly. 

Someone (on this list?) was talking about insulating all the connecting
pipes which makes good sense, another idea is to place an inline fan to
improve the flow at idle, a recirculating system also makes immense sense
(except for possible poisining if you are not careful). DC

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David Carment
School of International Affairs
Carleton University
Ottawa, Ontario
K1S 5B6
voice - (613) 788-2600-6662
fax - (613) 788-2889
Email address: dcarment@ccs.carleton.ca
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