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Sat May 01, 2004 3:21 pm

I think my voltage regulator is bad but I'm not sure. Is there any way to test it. How do they go bad. Thanks

Sat May 01, 2004 4:47 pm

What do you have - generator, alternator, 6V, 12V?

12V generator or alternator should give you about 14.5V at the battery at 2000-2500 RPM, anything above 15V is a bad regulator or bad connections, especially grounds.

Why do you think it's a bad reg? Low voltage is seldom a bad reg but it is possible.

Sat May 01, 2004 4:51 pm

ive been having trouble with that too my voltage is so low it barly ready i have a 12v generator and i hooked up a vat 40 to it and hardly read anything :cry: i feel your pain dstefun

Sat May 01, 2004 5:35 pm

supermanspence wrote: ive been having trouble with that too my voltage is so low it barly ready i have a 12v generator and i hooked up a vat 40 to it and hardly read anything :cry: i feel your pain dstefun

Sun VAT40 is usually an alternator/battery tester. Try these links for info on how to test your generator....

http://www.nls.net/mp/volks/htm/gen.htm

http://www.geocities.com/aussiebug1970/generator.html

Sat May 01, 2004 6:08 pm

I have a 12V generator, Its driving me crazy. I pulled the engine the other day to fix an oil leak. TOday /i put it back on hooked up everything. My battery was dead. SO i put in another battery started up but my battery isn't charging. Whatr would cause the drain in the battery and could this have killed the regulator.

Sat May 01, 2004 6:51 pm

ok then my next qestion is does the voltage regulator differ between 6v and 12v? or are they the same?....i have this on in my bug
[img]
http://thesamba.com/vw/forum/album_page.php?pic_id=60716[/img]

Sat May 01, 2004 6:55 pm

well that what mine looks like but im not sure if its for a alternator or a genaroator ...does that matter also?
...and i heart you have to polerrise a regulator before you put it in....is that true?...and how do you do it?
thanks

Sat May 01, 2004 9:04 pm

supermanspence wrote: well that what mine looks like but im not sure if its for a alternator or a genaroator ...does that matter also?
...and i heart you have to polerrise a regulator before you put it in....is that true?...and how do you do it?
thanks

Well I don't think the picture you posted is correct as an AL78 alternator regulator but it is what an early generator regulator looks like through 66.
There is also a 12V regulator that looks the same, and was used on busses.

From 67-73 beetle 12V generator regulators looked like this:

A regulator does not need to be polarized, but the generator does. Instructions are in either of the 2 links I posted above, as well as how to check your generator output.

Mon May 03, 2004 1:34 pm

Is there a way to fry or short out the regulator. When I disconnected the generator two wire touched for a second, could that effect the regulator at all.

Mon May 03, 2004 1:49 pm

Yes, a voltage regulator can fry. Here's a couple links to help your narrow down your problem. More fun links.

http://www.nls.net/mp/volks/htm/gen.htm

http://www.nls.net/mp/volks/pics/gen.jpg

I have never seen the regulator that Dstefun posted in the second picture. Are these new? Every 12V regulator I have seen, bought, replaced, looked like the one in the first pic. If it's 6V it mounts to the top of the Generator. If 12V, it should be under the back seat driver side. If you buy a new 12V regulator, replace your existing by pulling one wire at a time off of your old one, and putting the wire on your new one. It grounds through the body, so make sure the mounting points are nice and clean. If you've already pulled out your voltage regulator and pitched it, and your new one isn't marked, shoot me an e-mail and I'll send you a picture of one.