Ammeter reading charge

[leesmeade]

1929 tudor with 30 amp alternator and 30 amp ammeter.
Meter reads zero when engine off, when key turned on it read about - 1 amp. When started the battery recovers in a few seconds and the meter reads +10 amp and never returns to zero. The battery never discharges, both battery and alternator have been replaced and there are no accessories in the vehicle that could pull that kind of current. Does anyone have an idea as to why this happened overnight for no apparent reason?

[CSPIDY]

You can check the actual current draw with an induction style amp meter. You could have a bad or loose connection somewhere in your electrical system. Start at the battery.

[Purdy Swoft]

maybe the adjustable brush in the generator has moved and needs adjustment . pushing down on the third brush increases charge . Moving the brush upward decreases charge . If you aren't familiar with the three brush model A generator , look at some internal pictures of the brush setup to better understand how the third brush adjusts .

[Purdy Swoft]

Some how I missed or forgot that you are running an alternator . Disregard my post regarding the third brush adjustment . the alternators don't have an adjustable brush but usually have an internal voltage regulator .

[katy]

the alternators don't have an adjustable brush but usually have an internal voltage regulator .

Some, but not all, of those w/an internal regulator are adjustable.

[DHZIEMAN]

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What is the voltage at the battery with the 10 amp charge rate?

[Badpuppy]

When you switch on, the points will draw current if they are closed, which means, "usually". Check your points for pitting, just one amp seems a bit low.

[Tom Wesenberg]

Points closed and key on, the coil should draw about 4 amps.
The alternator is putting out too much voltage due to a bad regulator, if it never drops back to close to zero, or you might have a bad battery with shorted plates.
Try swapping batteries with another known good battery.

[WHN]

Originally Posted by Purdy Swoft

Some how I missed or forgot that you are running an alternator . Disregard my post regarding the third brush adjustment . the alternators don't have an adjustable brush but usually have an internal voltage regulator .

Still good advice for people running a generator.

[Purdy Swoft]

Thanks WHN !!!

[eagle]

Take battery voltage readings with a quality voltmeter. Check before you start and also on high idle. Get back to us with the readings and then we can help you with informed comments.

[leesmeade]

Violtage about 7 (seven)

[Jeff/Illinois]

I never got good readings with a digital voltmeter on a Model A Ford. It bounces all over the place.

Try an analog meter for accurate results.

[chap52]

I have a 30 amp alternator and a 30-30 ammeter also. After start-up, give the engine a "rev" to excite alt into operation. Should briefly show a charge then settle near zero.
If its a new alternator I would do as suggested and check the battery connections first. If still not functioning as it should...Then pull the battery out and take it a local auto parts store for a free load test.
Keep us posted,
Chap