Ammeter shows discharge but not charge
 

Hi Boffins

Please help:

I use my car as a daily driver in the Johannesburg traffic, but using it at night has become a huge problem as the battery does not charge up enough, so every time I get home I have to connect my 6v charger up so that the car will start in the morning.

Am going to give it a go to adjust the charge rate on the generator by apparently moving the "3rd brush" (whichever the hell that one is) clockwise...

But the other problem is that my ammeter is showing discharge, but not charge... it stays on zero when I am driving. But the genny must be charging otherwise my battery would be running down real fast.

Any help with this will be hugely appreciated.

Chris Van

Re: Ammeter shows discharge but not charge
 

Swap the wires on the meter and see if it will go the other way to eliminate the meter as the problem.

https://www.fordbarn.com/forum/showthread.php?t=3122

Re: Ammeter shows discharge but not charge
 

Okay Mike thanks will do that....

Re: Ammeter shows discharge but not charge
 

Before doing that, Take some voltage readings and get back to us. Then we can give you some feedback. 1. Voltage at battery when engine off, also with engine at a fast idle. 2. Voltage on both sides of the cutout with engine running at the same fast idle. 3. Fast idle again, check voltage at battery with lights on.

Ignore the underlined words, for some reason when I use this computer I get random words underlined.

Re: Ammeter shows discharge but not charge
 

Turn the lights on, or, just step on the brake pedal and see that the ammeter shows discharge. It should and then you'll know the ammeter is connected correctly.

When running normally with lights off does the ammeter show any charge ? It should a few amps. If so, then adjusting the third brush for more charge should take care of your problem. Adjust it for about 8-10 amp charge without the lights on. I don't like to see these generators set at more than 10 amps.

Re: Ammeter shows discharge but not charge
 

Posts 4 & 5 got it right

Re: Ammeter shows discharge but not charge
 

Try POLARIZING the generator.
Bill W.

Re: Ammeter shows discharge but not charge
 

Diagnose and verify before moving and adjusting

Re: Ammeter shows discharge but not charge
 

Thanks Mike, Eagle.

Okay I have an appointment at a buddy with a multi-meter on Monday and will do all the testing.

Will keep you posted.

Good weekend,

Chris

Re: Ammeter shows discharge but not charge
 

Key words used in the SEARCH feature are underlined, and misspelled words are underlined by spellcheck. Aside from these two reasons, I've also seen random times when a few words get underlined, and I have no idea why. Of course when it comes to computers, I'm no good.:mad:

Re: Ammeter shows discharge but not charge
 

Don't know whats going on with that, an hour ago the underlining was there, now its gone! Whatever...

Re: Ammeter shows discharge but not charge
 

Right on William!

Pluck

Re: Ammeter shows discharge but not charge
 

Not so. If your motor starts up really fast there is minimum drain on the battery and you can run for many days without a charge if not using your lights.

When we bought our Model A it had a duff generator but ran for over a month before letting us down. (I thought we had a bad ammeter, did not make the necessary checks:eek:)

Sounds like your generator, cut out/voltage regulator are not working correctly. Take the voltage readings as recommended above and report back.

Re: Ammeter shows discharge but not charge
 

Hi Guys
Thanks a billion for your comments. I was driving from Johannesburg, to Clarens (about 200 miles away) for to do a wedding and driving at about 55 to 60 mph (I do have the tall diff) but the oil level was only half and maybe if it had been full I would not have run big end #4! So there is this Model A boffin called Kevin Casey, who lives in Harrismith, who collected my car on a trailer (lucky we organized a substitute car for the wedding.. a '48 De Soto)... and when it was fixed he noticed my electrical problem... and Ian Simpson you are 100% correct... I had the points-type cutout switch but he said the points were not closing and the reason my battery was not dying because yes my car starts real quick and I charge it manually for night driving... but the points by natural vibration when you are driving do touch, sending a sliver of power to the battery. Anyways, Kevin chopped off the whole points thing and soldered in a nice fat diode (30A) and voila! it now charges like a wounded buffalo. He said the diode should last the life of the car provided I don't get the battery polarity wrong. Apologies for taking so long to reply but I had no way of sorting this out myself until the bearing went and the car got into the right hands. Btw I have joined the Model A Club of America. Thanks again guys and please don't see my tardiness in replyin as a lack of respect... I was at my wits' end and had nobody who wanted to touch the car because it is 6V.

Re: Ammeter shows discharge but not charge
 

Cool glad to hear you got it figured out. and yes the diode is a magical thing and cant really get stuck. Thanks for reporting back what you found and your fix was! Far too often we are left in the dark :(

Re: Ammeter shows discharge but not charge
 

All good, SS!

Re: Ammeter shows discharge but not charge
 

I had this same problem with my cut out. The Amp Meter showed discharge but never charge. I drove about 20 miles last fall and almost didn't make it home due to low battery. I took the cover off the cut out and observed that it was not closing when the car was running. When I closed it manually ( a sliver of wood) my amp meter showed charge. I installed a new cut out and no more problems.

Re: Ammeter shows discharge but not charge
 

Just installed a newly rebuilt generator. Getting "no" increase in amps on ammeter even after sliding the "middle' brush to its max in either direction. I assume the 3rd brush is the middle brush. Its the brush on the top when removing the cover. I know the ammeter is good. I get a discharge when I turn the lights on and it goes back to 0 (maybe even 1 amp positive). New 6 volt battery fully charged....6.3 volts reading on the output terminal of the (new solid state) cutout switch at fast idle. With 6.3 vdc (Fluke Multometer) you would think that I'd get a higher reading that 1 amp ximim on the ammeter. Ideas?

Re: Ammeter shows discharge but not charge
 

See #7 above. New generator.

Re: Ammeter shows discharge but not charge
 

Is your new cutout the one with a built in voltage regulator?


If it's just the diode regulator, then make sure the battery is installed with the correct + ground, and be sure to polarize the generator by applying 6 volts to the generator output post for 1 second. Just jump across the two cutout terminals for one second to polarize the generator.