Date: Mon, 10 Jul 1995 16:49:41 -0700
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Dennis Gentry <dennis@cpac.washington.edu>
Subject: Bus probs
Hi,
When I'm having mysterious problems with a car, my strategy is
usually to check quickly for problems with the ignition, then
fuel delivery, then air, then maybe mechanical bogosities (i.e.,
cracked piston or something). If that doesn't find the problem,
I go back and make sure everything is exactly right: I'll check
(and make correct) the spark plugs, wires, coil, distributor,
points, condenser, timing. Getting everything exactly right and
checking it can take a while, but once you're really sure
everything is perfect, it's time to move on to fuel: Check the
fuel supply into the carb, check for vacuum leaks (hoses or
cracks in the manifold, etc.), check the operation of the choke,
throttle, etc. If that's all OK, make sure the engine is
getting air. For example, my brother's Fiat was performing very
badly (he thought it was normal). When I changed the (obviously
very dirty) air filter, performance must have doubled. Finally,
if all of the above checks out OK, look for mechanical problems:
Check the compression, etc.
Occasionally I've done a tune-up on my bus and it's worked fine
for a while, but performance has quickly gotten worse (say,
within 20 or 200 miles). Sometimes it was the point gap
dropping quickly because I hadn't lubed the distributor cam
correctly and the follower was wearing away. Once I apparently
didn't tighten the distributor hold-down bolt enough and the
distributor had vibrated around, changing the timing. It's easy
to get crap in the points by over-lubing the distributor cam
follower (or by having fat, greasy fingers :). If you have a
bad condenser, the points can wear amazingly quickly, to where
the vehicle won't run.
I hope you can get this sucker going again! Do you have the
Muir book? It has some pretty good step-by-step procedures for
tracking down problems like this.
Dennis
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