For what its worth our 82 has gone through the very same process of
replacement except for the cv boots. The shift linkage boot at the
tranny, the main intake,  aux air regulator and spark plug
rubber seem especially prone. Judging from what was taken out of the van
before the new stuff went in, its a combination of oil and extremely high
heat that destroys the engine rubber. For example, the engine skirt was
very stiff and not sealing well, where oil had dripped from the filler and
where the exhaust was leaking (since replaced).

 One thing I did; when we got the new engine was
spray every piece of rubber on the van with protectant and just let it soak
in over night. It seems to help for those areas not exposed to high heat.

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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