Volts meter reads low?

[edward ericson]

So I finally got the instrument cluster all buttoned-up (mainly, anyway, still missing the instrument lights for the small gauges), turned the key to test her and…

http://bridgetmgtd.wordpress.com/2011/04/11/dash-wiring-2/

Volt meter goes only to 12. Now, mind y’all, it starts out at 10, and the “gen” light is now in working order (didn’t exist before??!! Holy cow!) so I’m pretty confident she’s getting charge.

Any chance my battery is dead? With that kind of startup?

I kind of doubt it, but I’ll try a different battery later. Any advice welcome.

[Mark Hendrickson]

Ed, does it have a generator or alternator?

VW generators will read lower than one with an alternator. It’s probably been like this forever and only now that you have a measuring “tool” it concerns you .

Got a multimeter? Check the output at the big fat (10 ga.?) voltage regulator wire that goes to the battery +.

 

 

[newkitman]

Ed,

By any chance did you remember to flash the generator? A lot of times when the generator has been disconnected for a long period of time or if its replaced, you must flash the generator to get it working electrically. Kind of like jolting it back to reality. Just something else to check.

Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The Shack

[mike]

be careful, you can be arrested for that

[newkitman]

No no. Flash…..not moon! 

Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The Shack

[edward ericson]

Thanks, guys. It’s a generator. Never “flashed” it; it’s been connected since I got it, and probably for 30 years prior. Brushes good, battery has been living nice for a year and a half, so I assume it’s been charging.

I’m thinking the meter ought to read 12 or 12.5 on the battery alone when i turn the key on–before the generator starts turning. Then, with the engine running, we should be at about 14, if everything’s on the up-and-up.

The gauge works–that is, it reads x volts with the ignition on and x+2 volts with the engine running, and the needle blips when I blow the horn or flip the headlights on or work the blinkers.

I just don’t like the numbers I’m seeing, and wonder if it’s the gauge or the battery.

Putting a fresh battery in there will tell the story. I’ll report back tonight.

[edward ericson]

Put a charged battery in; readings are about the same–11 volts at rest and 12 when running. Think the meter is about 1.2 volts off. 

[Mark Hendrickson]

Put a good voltmeter on it and see.

As you know generators put out voltage as the RPM increases and vice-versa.

VW generators are a little bit better than that thing on your old bicycle that rubbed against the tire to power that 1 candle power headlight and taillight 

I convert all my VW’s to alternator. It’s a simple swap too. Only two wires to hook up.

 

[edward ericson]

Thanks, Mark. I’ll do the alternator when/if I get into the engine. It’s $200 beyond the already ridiculously overstretched budget I allotted for this project. Besides, the thing works. I never had to charge the battery or nothing last year, even when using the headlights and CD player! At the same time!

Right on re the ‘use another voltmeter’ advice though. I actually have a multimeter & will run it over this sorry-ass project later this week. Gonna take a break tonight and maybe lay-in the padding and carpet. No pesky wires to cross, just sweet sweet glue smell!

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