'67 Beetle burning voltage regulators?

[kgrimm86]

Hi folks. I'm looking for a little guidance/help for a problem I'm having with my '67 and I apologize in advance for the rather long post.

I've had this car about a year and a half and the PO had told me he fixed it up for his son who drove it while he was in school. Not sure how long ago the "fix-up" was. I had no problems with it since I have owned it, except for now. I was driving home one night and switched on my high beams. The high-beam switch the PO put in is a push button mounted under the dash...the one on the column doesn't work. I also had the radio on at the time. Shortly after turning on the high beams, I smelled smoke that smelled like wires burning and my headlights got dim. I stopped and checked to see if I could see any signs of a shorted/melted wire and could find nothing anywhere so I continued home. Stupid me didn't realize the generator wasn't charging (despite the blaring red light on the speedo - DUH!) Long story short, my generator ended up being bad so I replaced both the generator AND the voltage regulator. Got it all back together this morning and started it up. Voltmeter showed it was charging again, generator light was out and all seemed fine...until the new voltage regulator started visibly smoking and the generator light came back on. Generator is good because I checked it after all this and it's putting out 36 volts at about 3000 rpm.

So, my question is this - anyone know what would be causing this to cook the voltage regulator?

Thanks!
Kevin

[glutamodo]

What kind of voltage regulators were these?

[6Kabrio7]

I once had the same problem when I cheaped out and bought an aftermarket voltage regulator. Make sure it is made by Bosch.
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67 Convertible July 67 Yukon Yellow
67 Sedan May 67 Zenith blue

[kgrimm86]

The one that the PO put in was the new style solid state by BOSCH. The one I replaced it with was the old style.

[6Kabrio7]

I see what you're saying now I have the newer Bosch style in my convertible and haven't had any problems.
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67 Convertible July 67 Yukon Yellow
67 Sedan May 67 Zenith blue

[kgrimm86]

[glutamodo]

The solid state style has been extremely reliable for me ever since I first started using them soon after they came out in the late 90s. No points to get pitted, stick or burn up, no varying intensity of headlights at night. No overcharging batteries and longer brush life.

The solid state ones, the unregulated geneator output (D+) is the entire top "cover" so beware to not hook up or let ANYthing else metal touch that when the engine is running. The dedicated ground - the brown wire that goes to the small screw on top of the generator housing, the other end of that wire, with the old style regulators there was a #31 ground screw, there is no such on the solid state type. So you put it under one of the mounting screws at the base.

I'd verify all three of those wires are good - each carries a signal with no resistance and no shorts between wires. That would require a multimeter. If the wires check out, and if you hook it up correctly, then it should run just fine unless you got some odd thing going with the generator. Sounds like the generator is working OK. Still, I might try the "motor" test on it - same hookup as polarizing, just need to have the fan belt off and the regulator not hooked up when you do it - the generator should spin fairly quickly in the normal engine direction.

-Andy

[kgrimm86]

[glutamodo]

Oh, I just remembered, this is a 1967. I'm not sure if they ran that dedicated ground wire that year! I think that might have gotten added in 1968 when they changed from the plug-in style generator to the bolt-on-terminal style. Or maybe even in 1969 when dedicated grounds were added to other items, like the turn signal bulbholders. VW never issued a revised wiring diagram after mid 68 or for 69, so it's hard to say. 1970 certainly had it though.

I mentioned it mostly out of habit - people could potentially see that wire and hook it up one of the extra top screws of the regulator, which would be a very bad idea!

Okay so your new to this. Continuity and resistance tests require you to put the two test leads to each end of the wire you are checking. I would NOT use the vehicle ground to loop this. What I use when testing continuity on items like this, since the ends of the wires to be checked are far apart, is a very long jumper wire I made.

Disconnect both ends, so for 61, unplug it from the bulb at the speedometer, and for D+ and DF, disconnect them from the generator. Then for each, take the long jumper wire clip one end to the disconnected end, run the wire around the car and through door and connect one end to your meter, connect the other lead to the other end of the wire you've chosen to test, then read the ohms - should be the same as the reading you'd get if you touch the two test leads together.

No, you should not polarize with the DF and D+ connected to the regulator! You can actually polarize it there under the back seat, disconnecting the two wires from the regulator, grounding the field and jumping D+ to the battery positive B+.

-Andy

[kgrimm86]

Thanks Andy! That's a HUGE help. Headed out to work now so I'll be checking this tomorrow. It's a pain in the butt that the Bug isn't working but like I said, working on them is half the fun of owning them LOL!

Kevin

[kgrimm86]

Andy,

I ran the tests on all the wires like you suggested. All of them tested OK so I'm assuming there are no shorts in the wires. The only questionable area in the wiring is the "dimmer switch" the PO installed instead of replacing the one on the turn signal lever. It's a push-button switch mounted under the dash and this is what I switched on just before I smelled wires burning which started this whole problem. Would you be able to tell me how to test that switch?

Thanks!
Kevin

[glutamodo]

Hmm, that is odd.

The headlight hi/low relay only needs its "S" terminal to be grounded to make the relay change states. The one on the turn switch has one wire that goes to a ground and the other to that S terminal on the relay. There shouldn't be anything hooked up that would draw enough current to make anything burn up or smell hot... all it does it energize an electromagnet that that stays energized as long as the switch is made. That's not a lot of current and I think you'd have to have power to it for quite long time before it would burn up. Still, any non-stock switch should best be a momentary switch, on that only makes contact when you press on it then de-energizes when you let up on it.

-Andy

[superpickle]

If it wasn't for this thread, and specifically glutamodo, I wouldn't know where that ground wire went from the regulator. The instructions with the new Botch voltage regulator are in Spanish and don't even mention it.
Thanks!!

[wcfvw69]

http://www.thesamba.com/vw/archives/info/wiring/bug_67_USA.jpg

If you go to the tabs at the top, go under the archives and you can find the electrical schematics for your year bug.

If it were me, I double check how the previous owner wired his aftermarket high beam switch. On a 67, they are on the turn signal indicator as you know. Many folks sell good, new turn signal switches including Wolfsburg West and others.

Trace all the wires to insure he's wired it correctly.
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