Generator/charging system woes

[90quattro20v]

Hello, all.

I am attempting to determine what is wrong with my charging system.

I bought new battery two months ago, and my 71 Super, which had been sitting but was in decent tune, fired up and drove great for a while. (I polarized the generator before installing the battery.) Now it will not start on its own, but I can jump start it and it will run/drive without issues until I key-off.

I am confused by the fact that it runs without problems. I do not think the battery is bad; my guess is that the generator is not charging the battery, but produces enough juice to keep my motor running.

When I put the leads across the battery posts, the meter reads 6-8 volts. When I check voltage between the two wires leading into the voltage regulator, I get close to 0 volts. When I put the meter leads on the two wires leading out of the VR, there is between 6-8 volts. I'm guessing this 6-8 comes from my dying battery, not from my generator.

How do I decide whether my generator or VR is broken?

Thanks for any guidance! (And please, do not ask me to run a search; I already did and couldn't find what I need.)

[PatterBon]

If your battery was in good shape, you could tell by how much the battery was being charged by. In my alternated beetle, the Voltage Regulator keeps the battery charged at 14.2v. If it exceeds 14.2v, the regulator is bad. But if the voltage is below 13.8v, then your charging system is to blame. The minimum is 13.8v for the battery to be charged.
_________________
PNW Dub Folk & Kitsap dub Folk (KdF)
Austin Aircoolers VW Gang
2020 Ford F-150
1973 Standard Beetle
1969 Cessna 172K Airplane
1959 Karmann Ghia
US Army CH-47 Chinook Helicopter Repairer

[cletus_zuber]

http://www.speedyjim.net/htm/gen.htm

a start
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1972 1302
HPMX 40's & 019

[90quattro20v]

Thanks. I will try this test again, with a little better jumper wire, and go from there. My expectation is that my generator is kaputt.

[Cusser]