Generator output only at idle

[Ed Saniewski]

The battery in my pickup has been loosing power for the last month, and I noticed that the amp meter only shows a charge at idle. As soon as I increase the RPM's the amp gauge drops to 0. I have a EVR in the cutout, and I have tried to change the third brush with the engine running, but it makes no difference. I changed out the EVR with a diode cutout and it seems the same. I don't understand how the generator can produce power at low idle only. Do I need to clean or adjust the brushes? Thanks.

[Tom Wesenberg]

That does seems strange, and the only thing I can think of is sticky brushes and an out of round commutator, but that would be highly unlikely. The only other thing I can think of is a loose connection where the higher RPM makes it loose contact.

[Patrick L.]

Have you tried feeding power to the generator to see if it motors ? If it does motor then chances are its good.

I'd recommend an original cutout with one of Tom Wesenburg's EVRs.


I'm thinking that this has been checked, the ammeter does show discharge when the lights are turned on engine not running.

[larrys40]

Ed,
yes that one's a little strange.. sometimes I've found that the 3rd brush just doesn't seat on the commutator and pulling it back and letting it pop back into the commutator it helps. You can use a reflective meter type voltmeter and do an actual check of the output. As tom said an out of round commutator can cause issues.
You may need to pull the generator to check it out. Of course make sure all your wire connections are in good shape.
Larry

[eagle]

Put a voltmeter on it and report back the readings.

[BILL WILLIAMSON]

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Is your Belt TIGHT?
Bill Loose

[Mitch//pa]

Yep I was thinking slipping belt also... Prob isn't though
Dad beat me to it

[Dick Steinkamp]

I've never seen a stock model a generator that will charge at idle. All I have seen show a discharge.

Could it be the generator is not working AND the ammeter is hooked up backwards?

[chap52]

Ammeter hooked up backwards?

[Tom Wesenberg]

My powerhouse charges at idle, which is about 500 RPM. Some guys like a real slow idle, and then it won't charge, but not charging during the small amount of time the engine idles is OK. A good generator should start putting out more than battery voltage at about 750 generator RPM, which is about 500 engine RPM.

[BILL WILLIAMSON]

Originally Posted by chap52

Ammeter hooked up backwards?

Ol Chap,
With the motor OFF, if it "charges" more when you turn on the lights, then it's wired assbackwards Chief used to wire his backwards, just for LAFFS Model A's are supposed to be FUN stuff!
Bill Backwards?

[Ed Saniewski]

So, it is the generator that is not putting out enough power. I switched it with a new generator and now get 6 volts out of the generator when at Idle. The EVR in the cut out is not working, so I installed a Ford cut out and set the amperage at 3 amps to keep the battery charged. Has anyone taken apart and rebuilt a EVR in the cut out. I will try and take it apart this week. The old generator must have damaged the EVR when it failed. Still have no idea why I would see a slight charge on the amp meter at idle, when I put an analog volt meter on it, it red zero volts. Thanks for the help. Ed S.

[katy]

Are you sure that its an EVR and not just a diode?

Ifn it's a Fun Projects EVR don't open it up, just send it back to FP and they will repair it free of charge. Ifn you open it up FP wont repair it free.

[Ed Saniewski]

Thanks Katy, I will write them and see if they can fix it. I did not think they would take it back.