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Tue Mar 08, 2005 9:55 am

This morning I went to start my car, and noticed the battery was dead. Made a click, and starter turned over, then nothing. So I gave myself a jump with my other car, and went to work with no problems. However, once I got to work, I tried to start up my car again and the battery was still dead. The last two weeks my Generator red light and Battery red light have been on - ever since I changed my coil (from the bosch black to a pertronix flamethrower coil). Now, I swapped them back, and got another jump, and my battery still does not charge and both those lights stay on. Anyone know what I should be looking in to? '72 Squareback with dual webers (and much problems) by the way. Thanks, Doug

P. S. - I had my battery checked about a month and a half ago and it was low on water in one of hte cells, so I filled it up, and they charged my battery and said it was good. This was after leaving the lights on all day at work.

Tue Mar 08, 2005 10:25 am

Do you mean the OIL and generator lights? Do they stay on even with the key off?

Tue Mar 08, 2005 10:54 am

On the right lower side there's a small circular light with a B on it, I assumed it meant battery. They turn off when I turn the car off.

Tue Mar 08, 2005 11:41 am

i think the B light goes on when the gen output drops below a set level. that is why it comes on when you turn the engine off. have you changed the brushes in the gen lately or try cleaning it up real good and see if that helps. other things it could be is a bad voltage regulator.

Tue Mar 08, 2005 11:57 am

Yeah, that's what the Muir book said to do. However, in the book, it describes the brushes as being in two slits near the pulley side (rear I assume) of the generator. Mine does not have those slits, but it has one big one at the front of the generator. Is the brush the piece of graphite (or whatever) attached to a wire and held in with a clip?

Another question - I read in another post there should only be two wires connected to the generator. However, when someone did the conversion from FI to dual carbs on my car, they left stranded wires everywhere. I connected one of em to my generator, because it looked like it had been frayed off (the clip was left on the generator). This of course was after all of this. I've got a multi-meter too, but I haven't checked anything w/ it.

Tue Mar 08, 2005 12:00 pm

The "B" light is the brake warning light. Because of the way it's wired, it'll come on WITH the alternator light. So what you have is a charging system problem- Generator, regulator, or ground. The first thing I'd do is make sure the regulator has a damn good ground. yes, the brush is what you describe. There's one at the top (the one you can see) and one at the bottom. You can loosen the gen. strap and turn the gen over to check the lower one. Make sure that you get the generator back into position so that the cooling hole in the gen. lines up with the cooling hole in the fan housing. Make some reference marks on the gen before you move it so that you get it back in the same position.

Tue Mar 08, 2005 2:18 pm

OK - both the brushes appear to be in good shape (no cracks, no big chunks missing) and connected. However, upon turning the generator upside down, I noticed that there was a pretty heavy gauge copper (?) wire with paper shield that the shield was pretty much gone from. Just flaking off all over.

As far as wiring goes, there is a big wire (from the Voltage Regulator) and a smaller black wire going to the D+ terminal. Nothing connected to the DF terminal. And a brown wire is connected to the generator body.

Tue Mar 08, 2005 2:43 pm

Nothing connected to DF is the problem. That should be the terminal the dash light is connected to. The F in DF stands for Field. The generator is an electromagnet with a coil of wire spinning inside it. With the DF wire disconnected, there's no electromagnet, just two coils of wire, so no charging. Normally, DF is wired through the dash light from power at the ignition switch. This way, the electromagnet is only active while the car is running. Once the generator is working, generating current, the light goes out because there's equal current both at the battery and at the electromagnet, so the voltage across the light bulb drops to 0, and it goes out. The DF wire on my car is green, but I have a '69, so the wire colors may have changed, but you should look for a small wire not connected to anything near the generator.

The big wire from the generator at D+ should go to the regulator. Another big wire should go from the regulator (different terminal) to the battery. The brown wire should go from the generator body to a ground point.

Tue Mar 08, 2005 3:38 pm

Yep, that's what it was! I supposed the two tell tale signs would have been the terminal coming out of the generator that wasn't connected to a wire, and the green frayed wire that was missing a terminal! The rest of the loose wires already had terminals on them.

Thanks tram and lapuwali (and karfer67)!