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Ok after reading some forum articals on wiring I am confused

I have 53 Clipper it has been converted to 12v. the neg cable is connected to the block and the positive is connected to the alternator. Is this correct? With the engine running the charge light goes off and on as you rev the engine. The car also has an electric fuel pump, it works fine now, will I need to rewire it also?

Dan, Your car was originaly a 6 volt positive ground system. It seems like whoever converted the car to 12 volt negative ground did so correctly if the car is charging the battery and the electric fuel pump is working.

Some alternators had a higher "Turn On" rpm that others. So if you are idleing at a low RPM, then it is possible that the alternator is not charging at that low RPM and that is why the charge light comes on.

The way the light works on most alternator is that one side is hooked to the Alternator sensor terminal, and the side to switched 12 volts. When the alternator is not turning, the light terminal on the alternator provides a ground, so the current flows from the switched 12volt and to the ground, and turns the light on. As the Alternator spins, it produces voltage, as the voltage rises, the light gets dimmer and dimmer, until the voltage being produced is equal to or greater that the volatge from the switched 12volt. At which point the light goes out. Also most charging light circuits have a diode in-line with them to keep the current flowing one-way.

So what you are seeing is that at idle the low RPMs are causing the Alternator to produce voltage lower than the voltage at the switched 12v and this causes the light to come back on. As you rev it, the alternator spins faster, the voltage it produces goes up, and the light turns back off.

They do make alternators with a lower RPM turn on rate, also changeing pulley diameter on the alternator so it spins faster can help.

Hope this information helps. Here is a '53 diagram I did awhile back for someone looking to convert their car to 12-

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Dan. What BRAND of alternator is it and how many wires are comming out of the back of the alternator. I'm guessing there is only ONE wire routed to the alternator.

If it was a one wire, then I doubt he would have a working dash light at all, as there would not be a terminal for it.

thanks for the drawing

I have 3 connections on my Alt 1 terminal on the back and
a plug on top with a red wrde on the left (looking toward the back ofthe car) and a black on the right. the hot lead from battery goes to the starter. I will use the drawing to see if I can trace the other wires.