10 ohm charging resister (Page 2/2)
rubyredfiero JUN 30, 09:38 AM
These are the readings I got at points 1 thru 6.

I hope #6 is low because there's a resister in series. Based on the voltages, is it correct in stating the alternator must be pulled out? This is not going to be fun for this old guy, but it must be done.
theogre JUN 30, 04:38 PM
Lets Assume you have a good meter and probes...

12.3v and engine running? = alt Not running.
Even wait a minute or three doing measurements still at 12.3v = alt is likely "dead."
Running Alt should be 14 - 15 v at all 12.3 points.
(Car w/ iffy wiring can jack alt out higher then 15 v because of big sense wire loop on 84 as covered in alt sense page.)

All meter grounds are on the engine or engine and frame?
If both likely means major grounds are ok since most are same v.

L wire will have less v because v-drop for resistor wire at minimum.

check Ω between alt out and starter. FL can "blow" w/o Frying off because wire and splices break.

Carefully check the "side plug" to the alt. Many are damaged and alt have problems.
Problem is it's a Metri-Pack "Pull to Seat" type and not easy to take apart and too small even then and likely wreck the pins getting them out.
See my Cave, Weater/Metri Pack notes plus have a clip very hard to see or release the pins.
So if it looks has damage, buy a pigtail and ignore I/F & P.

Metri-Pack "Pull to Seat" take apart should be covered in any FSM and others after ~ 87. Most don't bother trying even when have GM tools.
rubyredfiero JUL 01, 10:08 AM
theogre - appreciate the input and will try to answer some of your concerns:

Lets Assume you have a good meter and probes...
I use a digital power probe.

12.3v and engine running?
Yes, after any mods the voltage only dropped slightly, never up. Went for a 15 minute run with voltage dropping to 11.75v.

All meter grounds are on the engine or engine and frame?
Battery ground strap, 1" cradle strap and 6 ga chassis strap are attached to both cylinder heads. All the motor/trans mounts are solid steel.

check Ω between alt out and starter.
The fuselink wire is about 20" long and it measures 0.00 ohms.

Carefully check the "side plug" to the alt.
When I first switched the brown resister line from "F" to "L" and the result was still no charge, I replaced the connector with a new one which still gave me the same "no charge" condition. So now the alternator is out and today being CANADA DAY, I may disassemble it and check it using the FSM.
BTW - it took this old guy 6 hrs to remove it, due to the serpentine setup that have to be all done from under the car. But it's out.
rubyredfiero JUL 02, 03:18 PM
No charging condition SOLVED. I hope other peeps use this thread in the future, because I sure learned a lot from all the input provided. OK, OK. The alternator was the culprit, to be more specific, the voltage regulator had internal failure. This time it only took me 3 hrs to install the new alternator. That's twice as fast as taking it off.

So thank you all for the input. Too bad we can't edit the heading to add the word "SOLVED", or I don't know how to do it.

[This message has been edited by rubyredfiero (edited 07-02-2020).]