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Re: Will it work??- easy GM alt/reg test

To: efris@home.com, datsun-roadsters@autox.team.net
Subject: Re: Will it work??- easy GM alt/reg test
From: SPL311RDST@aol.com
Date: Tue, 18 Jul 2000 20:06:03 EDT
It really sounds like the alt. is overcharging (batt's AREN"T supposed to 
bubble!)

Quick hints for the GM internally reg alt:

With it on the car & running - stick a volt meter on the RED post. It should 
read 12.5-15 V. If it's higher, or lower bad reg. is possible.

Now look for a little "D" shaped hole in the back - a little bigger than the 
size of a pencil eraser. Inside you should see the shiny back of the voltage 
regulator. Take a screwdriver and stick it in the hole- touching it to the 
back of the reg & the side of the hole(alt case). This will ground the 
regulator and take it out of the loop. Check voltage again - it should jump 
up to 15.5-17.5 (Car running of course). This will test the output of the 
unregulated alternator. If it is way more (17.5 +), again you have a problem. 
If it doesn't jump up, then suspect the alt itself. (brushes usually for low 
or fluctuating voltage)

May wanna test this under different RPM & heat conditions, electronic goodies 
do weird stuff under extreme heat. 

May not help w/ your problem, but a good quick test to file for reference.

Someone else mentioned that your alt may not be internally regulated - here 
is the easy ID:
THe main plastic plug configuration of the INTERNALLY reg alt is
_ _

The EXTERNAL plug is:
I I

Simple enough.

Laurie :-)
70 SPL311
69 SRL311
Chandler, AZ

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