spitfires
[Top] [All Lists]

RE: Strange charging issue... STILL Not Fixed!

To: spitfires@autox.team.net
Subject: RE: Strange charging issue... STILL Not Fixed!
From: "John T. Blair" <jblair@exis.net>
Date: Thu, 20 May 1999 01:43:02 -0400
At 11:32 PM 5/19/99 -0400, Gregory W. Smith wrote:
>
>Having left my Haynes manual at work, I proceeded into additional
>diagnostics with... trepidation. (I'll have it tomorrow, though)
>
>Here's the latest:
>Voltmeter to gauge common ground, + to big brown wire on stock alternator
>Ammeter inline on + circuit for ALL current from battery (using 4 gauge new
>cables)
>
>If the car is off, I get 12-13v on the voltmeter. The big brown alternator
>wire is ALWAYS hot (it shares the same post on the starter relay with the
>battery + cable) This tells me battery voltage is 12-13v... OK
>
>If I turn the car on, but don't start it, voltage drops below 8 (scale is 8
>to 16v)
>If I start the car, voltage "flutters" from 8v up to battery max. Max drops
>as the battery discharges. It takes about 2-3 hours of driving (no lights)
>for the battery to discharge.
>If I hook up the voltmeter directly to the battery (+ and -) I get the
>expected ~12v
>So I'm showing the alternator-supplied current (I think)
>
>This WOULD explain why I couldn't get a relatively new radio to work in the
>car...
>
>Again, the alternator was tested (at Pep Boys) and puts out 15v for
>charging. They said that it's good.
>
>I was able to isolate the problem further, though.
>I started pulling fuses (no change) and pulling various leads to see what
>behaviour the result would be.
>
>When I pull the battery - cable, the car cuts off. The alternator is not
>putting out enough juice to run the car (but according to the test, it IS
>capable of doing just that)
>When I pulled off one of the LT - coil wires, the car also cut off. But my
>"flickering" gauge persisted. -8 to about 10v 4-5 times a second. It would
>stop if I disconnected the Molex(?) 9 pin plug to the steering column.
>
>***My best hypothesis is that the trouble is related to one of the smaller
>brown alternator wires. My ignition light does light while or just after
>starting the car, and stays on until the voltmeter begins its "flicker"
>cycle.
>
>Why would I be getting these symptoms? HELP!!!!!
>
>I did have some ground issues. Cleaning them up helped to make the problem
>"repeatable": far better for testing.
>
>Ammeter NEVER shows the vehicle charging. (except when I put my battery
>charger on at the end. That did show +6A for my 6A charger.

Gregory,

  Sounds like you have something shorting out.  Continue on your quest,
pull each of the fuses and see if that helps.  Then look at pulling the
harness apart any place you can, like where it goes to the headlights,
or branches down to go to the rear, etc.  See if you can get the voltage
to come up.  This is a real pain, but it sound like you have a wire that
is pinched somewhere and the insulation has been cut so the wire can touch
the metal body. 

Look at all the perpherials and disconnect them, for example the wiper
motor, the windshield washer motor, etc.

John


John T. Blair  WA4OHZ          email:  jblair@exis.net
Va. Beach, Va                  Phone:  (757) 495-8229

              48 TR1800    65 Morgan 4/4 Series V (B1109)
71 Saab Sonett III (71500840)    75 Bricklin SV1 (0887)    77 Spitfire

Morgan: www.team.net/www/morgan 
Bricklin: webus80.wang.com/BI (new adderss)



<Prev in Thread] Current Thread [Next in Thread>