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89 100 Wagon charging system woes :-(

Well....  I'm somewhat baffled at this point :-(

The facts:

Re-built Bosch Alternator 12 month's ago.
(beginning to think this may not have been
necessary :-( read further.....)

Battery confirmed good by Sears computerized
battery tester.

Pulled Jump Start post wire and Battery Positive
cable from Starter and cleaned with wire brush.

Battery connections clean.

Test Conditions:

Car running at idle.

Multimeter shows 14.0 volts at Jump Start post under the hood
grounded to the Intake Manifold, Strut Bolt or Ground of 
Battery post.  Yes I ran a wire all the way back to the Battery
ground just to be sure.

Multimeter shows 12.66 at Battery positive post when grounded to
the Intake Manifold, Strut Bolt or Ground of Battery post. 

Thought this odd, so I ohmed out the connection from the battery
post to the Jump Start post and it showed 0.000.

And you ask why am I doing all this ? because if I run the car
with the A/C on (aka constant running fan when A/C is on and
the fan usually runs after car is shut-off for 5-10 minutes.)

The car battery will be dead when I go to start it again.

After all this testing the reason the car dies is starting to make sense,
just enough juice from the alternator to trickle charge the battery but
not enough to get it really charged to sustain the fan when the car is not 

At this point I don't understand if the positive connection ohms out at 0 
how I can get different voltages at the Jump Start post versus the battery 

I'm almost at the point were I'm going to sacrafice a set of jumper cables
and go from the starter all the way back to the battery!

Anybody anything like this before ? am I missing something ?

Thanks for reading this far :-)

FYI, I'm not currently subscribed, please CC me at


Mike L.
89 100 Wagon
90 V8
* Mike LaRosa, Manager 
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