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Low alternator charge at idle

You need to measure voltage, not resistance.. And it should be done with everything connected & the engine running..

The picture shows how to back probe a connector... I use sewing needles.... They are using a fancy tool that they sell... My way is the old cheap way..

View attachment 1758411

Do you have a thimble or two around. Your quilting club must be pissed with the missing needles! :D

Awesome working hack using the sewing needles. Well done
 
Do you have a thimble or two around. Your quilting club must be pissed with the missing needles! :D

Awesome working hack using the sewing needles. Well done
Back when I was working in the trade lots of guys would use pins & needles... Many would go straight to puncturing the wires insulation... I always tried to back probe connectors but if that failed I would poke the insulation... Ya gotta get your test results to diagnose stuff somehow...
 
I read "resistance" in post # 94 and took it literally.
 
I read "resistance" in post # 94 and took it literally.

Thing is that blue wire going to the regulator is the reference voltage the the regulator needs to know when to force the alternator to charge... So if the wire has high resistance and the voltage going to the regulator is 2 volts low the alternator will charge 2 volts high....

The test should be looking for voltage drop... The reason for voltage drop is resistance... You could ohm the wire but the ohm meter may not push enough amperage through the wire to reveal a problem....
 
SUCCESS !

The adjustable voltage regulator arrived the other day along with the pigtail.

4B0B6497-3171-4DEC-BB28-3577D4B7A948.jpeg


Maybe they include the pigtail to allow owners of the 1969 and earlier cars the ease of installation?
The box had no instructions inside, just what you see here.

E1F6A8D7-5192-46F5-9E29-E7BDD5225908.jpeg


2318DEAE-92AC-4C6C-9233-71DC245E04D6.jpeg


5A28B315-43B9-457F-ADB9-3F2E1814DBAC.jpeg


Instructions were not necessary though. It has a slotted button on the back.

BCC575D7-AD1B-421B-9096-AE21C40013B5.jpeg


86635AEB-48EA-4D7A-8CE8-E1D04021646E.jpeg


083E47EA-94A5-48E8-B381-7688A3AB1D4A.jpeg


Hard to screw that up, right?

Before all of this, the other alternator and regulator had the car idling at around 14 volts with no lights or heater-A/C fan going. With those on, the volts dropped to 10-11. That is what motivated me to make changes.
The Tuff Stuff alternator and regulator helped a lot but went too far. I was at 15+ volts. I tried 2 other regulators and got the same reading. The wiring was good, everything is well grounded so I figured that this regulator would fix the issue.
BCEDBAD0-A83D-4464-8F87-F1A55FAD6025.jpeg


Fast idle but that is where it likes to be.

6A5D9110-5CED-4EE1-B8A0-629CF2BBCAEE.jpeg


The volts are where they need to be now too. At first, it was charging at 15 volts! I turned the button CCW and it went up to 16. Turning it clockwise brought it down to a slightly wavering 13.8 to 14.0. With the headlights on at idle, it drops to 13. A/C and lights drops only a little more. This will have to do. I tested at the terminals on the battery that is in the trunk.
I’d rather err on the side of caution rather than cook the battery and have to spring for another one.
Score !
 
SUCCESS !

The adjustable voltage regulator arrived the other day along with the pigtail.

View attachment 1760410

Maybe they include the pigtail to allow owners of the 1969 and earlier cars the ease of installation?
The box had no instructions inside, just what you see here.

View attachment 1760411

View attachment 1760412

View attachment 1760413

Instructions were not necessary though. It has a slotted button on the back.

View attachment 1760414

View attachment 1760415

View attachment 1760416

Hard to screw that up, right?

Before all of this, the other alternator and regulator had the car idling at around 14 volts with no lights or heater-A/C fan going. With those on, the volts dropped to 10-11. That is what motivated me to make changes.
The Tuff Stuff alternator and regulator helped a lot but went too far. I was at 15+ volts. I tried 2 other regulators and got the same reading. The wiring was good, everything is well grounded so I figured that this regulator would fix the issue.
View attachment 1760418

Fast idle but that is where it likes to be.

View attachment 1760417

The volts are where they need to be now too. At first, it was charging at 15 volts! I turned the button CCW and it went up to 16. Turning it clockwise brought it down to a slightly wavering 13.8 to 14.0. With the headlights on at idle, it drops to 13. A/C and lights drops only a little more. This will have to do. I tested at the terminals on the battery that is in the trunk.
I’d rather err on the side of caution rather than cook the battery and have to spring for another one.
Score !
I’m glad it worked out for you.
 
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