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Thu Nov 13, 2008 4:39 pm

Yes I've used the search. I've got a generator problem with my 1970 bay window. It has sat around in the driveway for about 15 years and after replacing almost everything it runs(ish). Anyhow about the generator
The gen light is on constantly and it is not charging. I tested the voltage across the terminals before and after starting the car to determine that.
I followed the diagnostic guide on this site http://www.nls.net/mp/volks/htm/gen.htm. So when i check the voltage out of the generator its about 5v and doesn't change when i rev the engine up. Here's the strange part it spun well when I polarized it. The fact that it runs that way would seem to suggest good windings. The brushes and commutator seem good and there's about a 1/2 inch of play in the belt. Any ideas?

-bill

Thu Nov 13, 2008 8:34 pm

Welcome.
Did you disconnect the regulator before you polarized it? Any chance a generator/regulator issue was why the bus was sitting for 15+ years?

Thu Nov 13, 2008 8:44 pm

While I generaly recommend sticking close to stock when it comes to vw engines, I fully recommend that you just upgrade to an alternator. You will get more juice and better reliability.

Thu Nov 13, 2008 10:43 pm

I agree, get an alternator. I had a lot of trouble trying to find a regulator for my generator because it was a 38 amp. Nobody had it so I just went ahead and purchased a Bosch alternator. I got it from Action Imports and they were really quick about the shipping. good luck

Fri Nov 14, 2008 4:37 am

If you can open your regulator you might try cleaning it. The contacts inside could have become stuck together after sitting for 15 years.

Fri Nov 14, 2008 5:31 am

agree,contacts in reg may need cleaning-they get this white corrosion after sitting for a long time.After cleaning u will see a relay that has open contacts when not running,this the one that pulls for gen to pass current to batt. Start engine and press this one closed,should stay on its own.Meter large post on gen while doing this,if gen working should go to anyway 13.5v or better depending on batt charge,fully charged batt should be 14-14.3 v as norm al. If relay wont stay pulled on its own and gen output as mentioned while holding contacts closed-probanly bad reg. Make sure small wire on gen in good shape/clean connection. Also being a gen u have to speed eng up to about 2k rpms to get any accurate readings on voltage.

Fri Nov 14, 2008 7:23 am

Many good suggestions already given here but I was just thinking that after 15 years your commutator might need to be cleaned. I alway used to use 600 grit wet or dry sand paper.

Fri Nov 14, 2008 9:35 am

Belive it or not i've tried all of that. I think i might try cleaning the commutator again. It can't be the regulator because i did my voltage tests while bypassing the regulator. The voltage that the generator itself is putting out is low.
To answer your question, the generator is not the reason it sat for 15 years. As far as i can tell the generator worked when it was put away. But so did most of the brake cylinders the carburetor and the distributor all of which I've replaced or rebuilt. My dad sucked a valve and then 10 years later replaced the engine, but didn't get around to repacing everything else that needed replacing after sitting for 10 years. He no reason to, he allready had a car. I've just moved back up to northern cali from socal with only a motorcycle and my goal is to have this thing running before it gets really cold and wet.

-bill

Fri Nov 14, 2008 9:51 am

bandaid wrote: Belive it or not i've tried all of that. I think i might try cleaning the commutator again. It can't be the regulator because i did my voltage tests while bypassing the regulator. The voltage that the generator itself is putting out is low.
To answer your question, the generator is not the reason it sat for 15 years. As far as i can tell the generator worked when it was put away. But so did most of the brake cylinders the carburetor and the distributor all of which I've replaced or rebuilt. My dad sucked a valve and then 10 years later replaced the engine, but didn't get around to repacing everything else that needed replacing after sitting for 10 years. He no reason to, he allready had a car. I've just moved back up to northern cali from socal with only a motorcycle and my goal is to have this thing running before it gets really cold and wet.

-bill

I vote for the alternator upgrade. Money well spent.

Fri Nov 14, 2008 12:15 pm

This thread may help:

http://www.thesamba.com/vw/forum/viewtopic.php?t=245285&highlight=generator+wire+broken

Fri Nov 14, 2008 3:21 pm

thanks for the link. You've convinced me to pull the MFer out of there and take it apart. It might save me $150 and if i still need to replace it I'll have already done the first step.
Edit: i know quite a bit about electric motors (generators are just motors running backwards) and i want an alternator soooo bad. That commutator bit is BS now that we know about the magic of silicone. But I'm moderately broke and if i can fix the inferior generator with it's ugly brushes, I'd like to, since it should be free to cheap as opposed to $200 for an alternator.
-bill

Fri Nov 14, 2008 3:23 pm

bandaid wrote: thanks for the link. You've convinced me to pull the MFer out of there and take it apart. It might save me $150 and if i still need to replace it I'll have already done the first step.

-bill

You're pulling the whole engine, right?

Fri Nov 14, 2008 3:26 pm

I haven't looked at the manual yet. Is that what i need to do to get it out. I'm running for my manual now.

edit: my manual says i need to partially remove the fan housing not the whole engine. Does it lie?

-bill

Fri Nov 14, 2008 3:30 pm

bandaid wrote: I haven't looked at the manual yet. Is that what i need to do to get it out. I'm running for my manual now.

In a 1968-1971 bus you have to pull the motor. In a bug you can do it but I think it's still easier to pull the motor.

Fri Nov 14, 2008 3:37 pm

Quote: In a 1968-1971 bus you have to pull the motor. In a bug you can do it but I think it's still easier to pull the motor.

Are you sure? In my manual it says you can partially remove the fan housing lift it and remove the generator. Partially removing the fan housing involves pulling the carb which involves completely disconnecting the wires from the distributor. Maybe it's easier to pull the engine, but i don't have a manual that shows me how to remove the generator by pulling the engine so I wouldn't know about that...

Fri Nov 14, 2008 3:40 pm

It can be done in the bus, but save yourself the contortions and drop the engine, everyone does it in the bus once and then learns. You probably need some new tin seals or fuel line anyways, do it all while it's out.

Fri Nov 14, 2008 4:10 pm

Good news bad news. I unbolted the face plate of the generator and found out that the df connection is bad and i probably just need to solder that in to get juice again. Bad news is that the bolts on the face plate have corresponding nuts in the fan housing and i heard the clink of them falling into the fan and now need to pull the generator anyway. Thanks for all the help you guys have saved me the cost of a new generator.

-bill

Fri Nov 14, 2008 4:53 pm

bandaid wrote: Good news bad news. I unbolted the face plate of the generator and found out that the df connection is bad and i probably just need to solder that in to get juice again. Bad news is that the bolts on the face plate have corresponding nuts in the fan housing and i heard the clink of them falling into the fan and now need to pull the generator anyway. Thanks for all the help you guys have saved me the cost of a new generator.

-bill

That's a very odd thing to have there. Pull the engine and fix all the problems and do the job right.

Fri Nov 14, 2008 7:03 pm

why is that odd? They have the nuts pictured in my manual and there was one on each bolt. You're right the engine did need to be pulled. The tin screws were just too hard to get off.

Fri Nov 14, 2008 7:31 pm

I put a hex head on the shroud screw on the left so I can remove it easier with a wrench. Makes lifting the shroud with engine in easier so I can remove gen and fan.