Discharge reading

B

bagpiper

Member
My '29 A has been sitting for several months. When I charged the battery and started it up, the ammeter shows between 10 and 20 on the discharge scale. The higher the RPM the more discharge it shows. I turned it off and left it for the time being. The ammeter gauge was working properly the last time I drove the car. What gives?
 
Paul, the battery is still installed as when I bought the car. I guess I don't know what the cutout is. I have charged the battery before with no problems.
 
The cutout is the little round silver device on top of the generator. Tap on it a couple times with a screwdriver handle and see if that loosens the points up that are inside the cutout.

Or does your car have an alternator?
 
Luke, Thanks for the info. It does not have an alternator. I'll try what you suggested in the morning. If tapping doesn't do the trick, can the cutout box be opened to check the points?
 
Yes- disconnect the battery, remove the wires leading to the cutout, and when you take the screws out of the front & back the cover will slide off the base. It may take some doing to get the cover off if it's been on there a while.

There is a possibility the cutout is solid state(no contact points but a diode) but you can't tell until you get the cover off.
 
You may want to check the batters plus an minus with a meter, I know somebody
who had a dead batt., and charged it backwards....and it worked !! The amp meter
worked backwards. The fix was killing the batt. with the lights and recharging the
batt. correctly.

Dudley
 
1st. How old is your batt?, Take it to an auto-zone and have it checked.
When i started having gen. and cutout problems about a year ago i went to a 6 volt one wire alt. no more problem's, Would never go back to that peskey Gen. ;). JMHO
 
Check for the correct battery polarity by turning on the headlights without starting the engine. You should get about 10 amps discharge. My guess is that you charged the battery backwards. Post your results.

Charlie Stephens
 
If the battery starts the car---don't worry about the battery.
With the engine off, blow the horn or turn on the lights to see if the amp guage shows discharge. IF it does, then POLARIZE the generator. Just take a short wire and jump the two terminals on the generatior cutout for about one second. Now start the engine and see if you get a charge.

If still no charge then jump the cutout terminals with the engine running to see if it will charge. If it does then the cutout needs repair or it's contacts need to be cleaned.
 
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LukeDahlinger said:
Yes- disconnect the battery, remove the wires leading to the cutout, and when you take the screws out of the front & back the cover will slide off the base. It may take some doing to get the cover off if it's been on there a while.

There is a possibility the cutout is solid state(no contact points but a diode) but you can't tell until you get the cover off.
Click to expand...

FYI the covers on original cutouts are spot welded on and not easily removable.
 
Tom, You said to check the ammeter to see if it shows discharge when the lights are turned on. It doesn't. It shows CHARGE when the lights are turned on. I also double checked the battery connections and the polarity on the battery. I have a good Fluke meter, so I trust it. Did I read your post correctly? I took the cutout off and it must be solid state. It appears to be sealed. There are 2 screws on the underside. There are three wires on the cutout, all connected to one terminal. I have made no changes to the wiring since buying the car, and it ran fine and showed a modest + reading the last time I drove it. The battery shows 6.28 volts.
 
Tom, after giving my pea brain time to work, I now see what you mean about taking the cutout apart. I asume that the two screws on the underside are to hold the points in place. Have a tire going flat on my P.U. and have to go get it repaired and then will attack the A again.
 
Charlie, I have checked the polarity on the battery and it is correct. I also checked continuity from the negative cable to ground and it is continuous. Is there something that I don't understand about a positive ground system?
 
Can you post a picture of the top and bottom of your cutout. With 2 screws it may be an original, which is the only cutouts I use. If the amp guage shows "CHARGE" with the lights on and engine off, either the battery is connected backwards or the amp meter is connected backwards. Some repro amp meters read backwards from an original, so you have to switch the 2 wires on the back of the guage.
 
Tom, Thank you for hanging in there with me. I have made no changes whatsoever to the charging or the wiring system since I bought the car. It was working properly the last time I drove the car. The battery is showing 6.28 volts with the polarity correct.
 
Is your ammeter wired backwards?

The meter will move in the opposite direction if it is.

My diagram shows the yellow battery wire should go the left terminal of the ammeter (looking at the face of the ammeter).

The dash light and yellow with black tracer go to the right side.



AND.... Tom beat me to it. Again. :)
 
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