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Can a car run off the Generator?

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vping

vping

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A few weeks ago I had left the lights on for a minute and the car was dead. I pulled and charged the battery and for a week on the bench it has been holding steady at 12.9 volts more or less. I posted about it here https://www.britishcarforum.com/bcforum/u...one_#Post637012

I will put it back in the car, start it and test the generator to see what the output is.

The question is can I start it and disconnect the battery and have it run on it's own like an alternator car? I learned when I was younger that a quick test of an alternator was to get the car started and then pull the + battery cable off. If it died, the alternator was NG. I do not know if this is a test that will work with a generator.

Vince
 
An alternator develops it's max output at low revs while a generator starts low and increases output with increased revs. So, a car will run off the generator, it just may require a higher idle. If you disconnect the battery with that in mind and it dies, then either the generator or regulator or both are probably at fault. I say probably since there's always the possibility there could be a intermittant fault in the wiring or ignition switch or such.
 
I'd be for simply putting a VOM on the battery and rev the engine to 2K~2.5K and observe the reading. 13+V means the genny is gennin'. 12.5V or less, the thing is in need of service. A good quick fix is usually to clean the comm with some "red" ScotchBrite and install new brushes. Clean the control box contacts with the same ScotchBrite.
 
Oh, lordy.
Pull the cable on an alternator, it goes wide open, and usually fries itself.
NEVER, as in EVER, disconnect the battery in an alternator equipped vehicle unless you plan on replacing the alternator within the hour.

Generator systems, all day long.

Once the cutout relay picks up, you can disconnect the battery, remove it from the car, and install the one needed to be charged.

The only real caveat is, make absolutely certain the hot cable (whether it be + or - ground, the cable not gounded) never, as in ever, touches the chassis or anything of ground potential while running, or you will be replacing parts.

Dave
 
David_DuBois said:
Vince - There aer better ways to test the generator and regulator. See the article, Testing a Dynamo/Generator in the Other Tech Articles section of my web site at: https://homepages.donobi.net/sufuelpumps/
Cheers,
Click to expand...

Thanks. Printed and I'm reading them now. I like adding articles like this to the "binder of priceless info" I keep about our buggies.

Car started and ran fine last night so tonight I'll do some testing. It's finally back in the mid to lower 40's around here so I'm thawing out a bit!!!
 
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