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Sun Dec 07, 2008 2:24 pm

I've got another related post to this, but figured I may get a quicker answer to this by posting a new one...

I noticed my generator vadiating heat and giving off that "elecrical smell" when I put my rebuilt engine back in. Tested all wires, tried a new regulator etc.

Took the fan belt off and polarized the gen. Put the wires back on to see if that fixed it. The gen started spinning as soon as I turned the key on. I'm guessing this is what was causing the heat and smell while the belt was on. It's trying to spin but of course dosen't have enough power to move the crank shaft pully.

The D+ connection is getting 12volts of power from the regulator as soon as the key is turned on. I would think the gen should be pushing power not using it. Almost like it's running backwards??? This is the last thing I need to get done so I can finally start the car and get it out of my garage.

Sun Dec 07, 2008 2:59 pm

I still think there is something wrong in your "wiring" of the car... your correct, this should not be happening. ( obviously I know but) I feel your pain... even for those of us who have worked on these cars for years and years there are situations like this where some wiring problems can "kick your ass"... no easy solution I can think of but stay calm and back track the related ( and then even "not related) wiring from one end to the other and again...

I wish I could tell you where to look specifically but IMHO and experience you just have to start checking and isolating each wire and circuit for mis match or "crossover" voltage source where there should not be one.

I would start with any big red from ignition swith, fuse block, headlight, charging circuit myself.

Sun Dec 07, 2008 3:09 pm

So what should go on with the regulator when the key is turned? Should there be power going to the D+ terminal? All my other electical (lights, flashers, wiper, etc) work.k

Sun Dec 07, 2008 9:03 pm

Anyone ever heard of the connectors being opposite on the gen? As a last resort I put the D+ from the regulator on to the DF and the DF on to the D+. No loud bangs, no smoke, and no generator spinning.

Is this a possibility or am I just hoping for an easy fix?

No one has been able to answer if the D+ wire from the regulator to the generator should be hot? I would expect this wire to carry power back to the regulator while the engine is running. In my case, it is sending 12volts to the generator. If i disconnect the dash light wire from 61 no power is sent and of course no dash light. Not knowing exactly what should be going on at the regulator has me second guessing everything now.

Sun Dec 07, 2008 9:16 pm

Many years ago a few drag guys I knew would purposely polarize the generator in reverse to use as a fan between rounds.

Here is the way to correctly polarize a gen for charging duty.

Is this the method you used?

More info here.

http://www.vw-resource.com/generator.html#polarize

Sun Dec 07, 2008 9:33 pm

Yes, but I didn't do it through the regulator. I took the wires off the generator and then used two jumpers. One on DF to ground and one on D+ to the battery. I did it for about three seconds and it did start to spin.

Sun Dec 07, 2008 9:40 pm

Merling wrote: Yes, but I didn't do it through the regulator. I took the wires off the generator and then used two jumpers. One on DF to ground and one on D+ to the battery. I did it for about three seconds and it did start to spin.

Now put the fan belt back on, leave the DF terminal grounded, and check for the high voltage from D+ to ground with the engine running at high rpm. If you don't get the high voltage (up to 35 volts for the 12-volt generator or 20 volts for the 6-volt generator), the generator is probably faulty.

If you get the full voltage, but when it's all connected back up and you don't see the normal charge voltage at the battery (14.5 volts for 12-volt generators or 7.2 volts for the 6-volt generator), the regulator is probably faulty.

Sun Dec 07, 2008 9:56 pm

But the issue is still there. When I turn the key on, the generator starts to spin. It should just sit there correct??? My D+ wire from the regulator is carrying 12volts to the D+ terminal on the generator and the generator is spinning like an electric motor.

Why would the regulator need power going to it if its job is to create power and send it back to the battery?

Sun Dec 07, 2008 10:57 pm

Merling wrote: But the issue is still there. When I turn the key on, the generator starts to spin. It should just sit there correct??? My D+ wire from the regulator is carrying 12volts to the D+ terminal on the generator and the generator is spinning like an electric motor.

Why would the regulator need power going to it if its job is to create power and send it back to the battery?

If you have everything back where it belongs you should not have voltage. Either a diode is bad or an armature is stuck in the regulator. Try tapping on the regulator cover with the engine running. Just don't leave it for long or you can damage the Gen. If you are sure the wiring is correct and you can not free the armature then replace it.

Sun Dec 07, 2008 11:11 pm

Appreciate all the help Viande. So no voltage / power going to the generator from the regulator along the D+ wire then. That's a big help. I can disconnect the gen wires and use my test light until I get the dash light on without power going down the D+ wire.

Tue Dec 09, 2008 9:53 pm

WTF!!! I have been looking at the wiring, double checking the diagrams, driving back and forth to the parts store and asking everyone I know about this issue. Everything I have tried still leaves me with power down the D+ wire and the generate spins like a motor. I've got two new regulators and each does the same thing. Got a new battery today because mine wouldn't hold a charge and same thing. I've got all the electrical disconnected except the battery, ingition, and regulator, still no luck.

Tue Dec 09, 2008 10:13 pm

What year is your car and if mid 70's where have you got the small black wire connected at the generator?

Tue Dec 09, 2008 10:38 pm

It's a 68. I've got it setup per the diagram...D+ to D+, DF to DF, and ground to the little screw at the back of the Gen case.

Tue Nov 10, 2009 12:18 pm

Yes it's been a while, but somone sent me a message if I had resolved this and I did so figured I should close this out...

It was a wiring issue. I have the street works wiring kit and I had power going directly to the gen and oil lights instead of having power going to the speedo itself (that connection at the bottom of the speedo that hooks into the gen, oil, and turn signal lights). I had a ground wire going to that speedo connection. I removed the hot wires from the gen and oil lights so the wires started at the lights and went directly to the regular and oil switch. I then put a hot wire on the speedo and that solved it.

Tue Nov 10, 2009 12:34 pm

Never mind.