Hello all.

I have a 1971 Super Beetle with a replacement 1971 1600 motor, carbureted, 12v Alternator setup, not generator. The car is somewhat new to me, and is my first Beetle. To give you an idea of what I have, the previous owner had lined the roof and firewall/behind-the-seat area with carpet. House carpet. Rental-apartment-complex beige berber - you know the kind. With lots and lots of cardboard and spray foam. Lots. The really flammable kind. Needless to say I have spent a LOT of time de-previousowner-ifying this car, which is otherwise in pretty nice shape. Mostly.

Two weeks after buying this car, the motor blew out - threw a rod. I shortly afterwards found a VERY nice motor of the same kind, and with help got it put in. It has been essentially trouble-free for months. I have been focused on getting steering and suspension straightened out and flying right, and had begun working on the interior when...

Recently, I have been experiencing voltage drops. Typically, the Voltage Meter reads a nice strong 14v when running. However, a couple weeks ago, it suddenly dropped while I was driving at night, and then died very conveniently on The Long Bridge south of town. I __BARELY__ made it off the bridge, rolling.

Hours later, after re-twisting together several loose wires under the rear seat and getting a jump start, I got the beast-le home.

Then commenced operation Fix That Hellacious Wiring. To give you an idea, some wires had been connected with taped-on female spade connectors. That means, two wires, each with female spade connectors, each of which had been slid into the side of a third larger not-connected-to-anything-else female spade connector. Several large-guage wires had been [badly] twisted together, and were almost totally loose. Some connections weren't taped - un-insulated.

That's all nice and tidy now with a wiring terminal.

Same with the old wiring terminal on the firewall in the engine compartment - replaced the terminal, replaced lots of old wires, replaced EVERY spade or ring connector, crimped right, and insulated.

And then a whole bunch of wires up under the bonnet, but not yet all of them.

The thing is, I am still getting the voltage drop. And I am running out of money to buy wire.

I have had the alternator [which is pretty brand new anyway] and the voltage regulator [internal to the alt] tested, and they are "working perfectly".

Here's what happens:

Each time I start the car after it's been sitting some time, it fires up [cold but running]. 14v hot and solid. I drive down the road - bumpy or smooth, fast or slow, wipers & lights ['tis the season], brake lights, blinkers, whatever - the Beast-le is happy as a clam at 14v. Until I get into town. This is a nine mile drive. Almost like clockwork, as I get into town, and I look over and see that the voltage has dropped down to about 12v, and sinks to about 11v or so by the time I get to work.

Starting the Beast-le after it's been sitting a _short_ time does not "restore" the voltage to working levels.

This leads me to think something temperature related. But what could it be?

The good news is that after re-wiring all the "wiring" underneath the rear seat, I no longer LOSE the battery - it just sinks down around, 11v or so and stays there. However, I have not gone for a longer distance to see if it eventually sinks further, as I don't get super excited about getting stranded out somewhere between No and Where, especially this time of year. However, using turn signals, headlights, wipers does make it drop a little, as is to be expected, but does not seem to actually _drain_.

All this leads me to believe that there is probably a faulty part or a short somewhere, and seemingly temperature related.

I have tried starting it, idling, and then pulling/pushing on wires to see if I can find a bad connection that causes the drop. I haven't found it yet. I am hoping that someone here who has a more comprehensive understanding of these solid little cars might have an idea of where I can look. I _could_ just replace all the wires, but as I said, I just don't have that kind of money to buy all that copper.
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First off just how old is the battery because what you describe sounds kind of like the symptoms of a bad battery... get it load tested and find out. Next get out the sand paper and go spend a night with you Bug, every plug-in and connector... Clean it, a 40 year old wiring system builds up corrosion on those connectors and this is something you should do every few years anyway.
66 Ghia, "Dexter" 76 flat window Beetle
It's not a Car it's a VolksWagon!
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Okay, I will check the battery. Yes, it's non-new, but didn't overly suspect it.

I will continue to clean contacts and replace connectors & wires as necessary.

I took it for an extended drive this evening. Steady at 14v until The Event; 11v steady even with running lights, but the headlights made it dip down under 10v. Had to off the lights and head back.

Nothing surprising there - looking kind of consistent, actually.

Maybe the battery. Thank you for the reply.
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Could this be the coil, acting funky as it gets hot? The battery tests okay.

As a note, the voltage drop I am seeing is sudden, not gradual. 14v, 14v, 14v, and then very abruptly down to 12v and _then_ gradually down to 11v.
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Is there some sort of charging relay somewhere other than the one in the alternator?

I am noticing that the voltage drop seems concurrent with engine temp.

Following some more wires, I found that the ground wire from the alternator travels to the terminal block on the left of the motor, and from there through the side of the firewall bundle into the rear seat well, where it finally is grounded to the frame.

Is there a good reason to travel that distance just for a ground, as opposed to just grounding it in the engine bay?
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