C1 Ammeter shows discharge!

[Don Izzo]

Just finished my restoration of my 60 and find that the ammerter shows discharge when the car is reved. I have read some threads in the archives about polorizing the generator/regulator (which I did not do!) as well as the ammeter gauge wiring in the shop manual being incorrect thus resulting in the gauge reading backwards?? I wired the ammeter just as the schematic appears in Nolands book, which I think is the same in the service manual. What gives? any help is appreciated.

Don in NY

[William C.]

Re: C1 Ammeter shows discharge!

Check the voltage at the battery while the engine is reved up some (2500 will do) if you see 13 volts or more, reverse the wires on the mmmeter, another way to check is leave the engine off and turn on the headlamps and step on the brake. If the needel moves to the positive under thses conditions, you have a 100% certanty you are wired backwards at the ammeter. Yes the factory diagrams are incorrect.

[Ed Jennings]

Re: C1 Ammeter shows discharge!

The 3 or 4 red/pink wires go on the inboard treminal towards the steering column. The black on the outside. If you didn't polarize the generator, there is a 50/50 chance it may not function properly. Sometimes they do, sometimes they don't.

[Don Izzo]

Re: C1 Ammeter shows discharge!

All right, I checked the wiring at the ammeter and the red wires are inboard closest to the stearing column, the black wire is outboard farthest from the column. Then I turned the headlight switch on and stepped on the brakes with the key off and the gauge needle moves towards the positive! I am not sure how to polorize the generator, can someone walk me through ( it's been decades since I had to do this!)

Don in NY

[William C.]

Re: C1 Ammeter shows discharge!

Polarizing the generator can easily be accomplished by using a wire to momentarly jumper across the "GEN" and BAT terminals at the regulator. it only takes a second, but from your gage reading, you are wired backwards. I'd fix that as you may be charging normally already You should see movement to the NEG or discharge with load (lights Brake light etc) when the engine is not running if correctly wired at the gauge.

[Mike M.]

Re: C1 Ammeter shows discharge!

I suspect some of the electrical engineers amongst us won't approve of how i determine if a generator or alternator is charging, but here goes: fire the puppy up then momentarily disconnect the Neg battery cable. if engine stumbles or shuts off entirely, the charging system is not generating electrons. if the old small block or big block continues to purr with the battery cable disconnected, the charging system is producing electricity and the amp gauge is malfuntioning.A couple of seconds of battery cable disconnect is adequate for the test and has never injured charging systems using this simple test.