Date:         Fri, 21 Dec 2007 16:36:32 -0500
Reply-To:     James Henry <jch@JCHGIS.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         James Henry <jch@JCHGIS.COM>
Subject:      An interesting repair sequence
Content-Type: text/plain; charset="us-ascii"

I have been struggling for months to make my "spare engine" in my 84 westy
work well enough to let me feel that I could work on its original engine. or
do a subie replacement. I got this engine for free from someone who had
describe it operation as "weird problems" and had given up and installed a
subaru.

It would run well at times, but had an intermittent lose of power, seeming
to to lose a cylinder, and firing in the manifold. Timing seemed to change
to something very wrong. I have been trying to diagnose the problem(s) for a
year and a half, did have some benefit from adjusting things on the throttle
body and related controls, but nothing that really fixed it.

So then I fixed it, I think......

The first immediate "FIX ME NOW OR ELSE" problem was a MASSIVE fuel leak
right after the fuel filter.  This seemed to be the result of a cobbled
repair by a shop used by the PO that has been the source of most of my
problems with this van.  The new fuel line and filter actually seemed to
result in engine running better, not sure how this was, do not think I had a
fuel leak for more that a few minutes, but ...

And then it seems that the battery was dead because it sat with the door
open, and I had to jump it, and it did not charge up like I expected. Drove
it 100 miles, still not a good charge.  No voltage warning light, but I
checked the voltage at the battery when engine was running, 12 volts!!!!
checked voltage at alternator, 12 volts!!!!!  The engine is supposed to be
under 100k miles but it had a rebuilt alternator from a shop in Oklahoma. I
guess that a low voltage state. I swapped out the alternator from my
original engine and, my goodness, not only does the battery charge, but the
intermittent problems have been missing for the first 50 miles! (A little
idle surging, but I think I can find that in the archives:-)

So not only are grounds important, but the idea that voltage can be less
than adequate and not have a idiot light say that you have a problem. And if
you start with a pretty good charge on your battery, it can stay reasonably
charged from driving.

Question: does the computer on a 1.9 "learn" and set up a "standard" state
that it then adjusts from so that it seems to run better over time? I have
heard of this happening on other cars, and would have the evolution of
better behavior as driven more miles.

Anyway, the lesson here is check both end of the electrical process, grounds
and the output of the alternator with your volt/ohm meter every now and
then, or install the voltage meter next to your oil pressure gauge. (I have
neither gauge, but they are on my wish list) .

Merry Christmas all.

Jim Henry
Durham, NC
84 Westy
85 Mazda RX 7 GSL SE