67 beetle new alternator keeps killing my battery

[Broke67beetle]

So I had the car running no problem it had generator and regulator that I had installed
My wires in the engine bay were heat rotted and the chrome heat shield was pinching them

I was concerned that I wouldn't be able to work on the wiring without breaking it. So i figured the mechanic I have been using would be a better option, just to neaten things up and put a grommet through the metal heat shield

I get the car back

he fix the horn, put a new turn signal relay and neated up the wires, it actually looks really nice. And probably some other things. I'm not really sure he kind of had his hands in everything.

Driving at home seems decent. Stop to buy my work and the generator light stayed on when I turn off the key. Turn on the key, only the oil pressure light so by the time I went a it to get some tools.
( I work at an auto parts store)
The generator is smoking i pulled the wires off the generator. I think the light was even still on so I pulled the battery terminals.
Call the guy, he picks up the car. Said that I should put an alternator in there that it'll fix my problem.
I'm not really sure what all has been done to the car, so I figure why not put the alternator in but now the battery just keeps dying. He says the battery is bad. Battery tests good.

So I guess my question is, where do I even start
Something is drawing power with the car off
I know nothing is supposed to work with key off except the headlights
The horn will work with the key off would that be enough to kill the battery?
I did install a cigarette lighter but I don't think that gets constant power.

He did say there was a parasitic draw of like, point something
i do believe beetles are supposed to have.No parasitic draw

I do believe if I take it back. There he's just going to put a brand new wiring harness in the entire car. I'm not really excited how about doing that?

I'm thinking about just asking him what system had the parasitic draw
I don't really know how a parasitic draw. Test works.
Would he know which system was drawing power? Or is it just like a general test ?

Thinking about adding a battery shut off there were a couple different options. I was looking at online. One of them has like a key fob any recommendations?

[slayer61]

Parasitic draw test is easy. Break the + connection at the battery, put your ammeter across the battery stud and the clamp and the cable. If you have current flow, you have a parasitic draw. If you do, go to the Fuse box and redo the test on each fuse location looking for the draw. Good luck!
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[zerotofifty]

The mechanic is defective. He created a problem, smoked your generator, installs an alternator, now he is blaming your battery which you say tests good, now a new wire harness is what he wants? As long as he has his hands on it, it will be a money pit.
_________________
Sorry About That Chief.

Give Peace a Chance.

Words to live by.

[Broke67beetle]

If that's the case, what do you recommend?
I honestly think it might be beyond my understanding at this point.
I do have some pictures of original wiring up front.
And in the rear
Could potentially try to remove everything, put it back
And start from scratch, but I'm pretty sure the generator's fried.
I'm not even sure I got the. Regulator back, but that was toast inside. It was all melted.
It's really hard when you have something. Somebody's messed with to know what it is. They actually did.
I do know beetle wiring is fairly simple, but most of my wires were painted purple, so yeah, it will literally be a shot in the dark.

[wagen19]

[mukluk]

The generator light staying on with the ignition switched off indicates that the voltage regulator cut in contacts stuck closed. When this happens the battery will try to spin the generator as if it were an electric motor, which will create quite a bit of heat and can burn up the generator if left as is for anything more than a brief period of time as you found out.

That said, there is no way to say with any certainty whatsoever that the failure was the fault of the mechanic. Looking at the picture in your gallery of the new regulator that was installed shows that it appears to be a new aftermarket unit, and sadly most of these tend to be quite poor quality from the get go. Crappy aftermarket parts is by far the most likely explanation for what happened.

Fast forward to your new alternator and its apparent power off draw killing your battery. I'd bet dollars to donuts that your new alternator is also a cheap aftermarket unit of very dubious quality, and that one of the diodes is garbage which will lead to the battery getting drained when parked. Crappy parts strike again.

Maybe it is time to find a different mechanic, but then again, what if this is the best one you'll find in your area? Human nature has a tendency to make people immediately jump to the conclusion they're being screwed over or want to place blame for events that are likely just happenstance.

Before jumping directly into panic mode and throwing parts, time, and money at the issue, I'd recommend for now just disconnect the ground cable from the battery while the car is parked and focus on learning how the electrical systems on your car work. With added knowledge you'll be in a better position to decide what's the best way forward to fix the issue or it'll give you the confidence to fix it yourself.
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1960 Ragtop w/Semaphores "Inga"

[Broke67beetle]

[my3bugs]

i believe that to be the best original pump , its rebuild-able unlike the new disposable garbage sold today . he was right about keeping that !!! its called a square top pump in the hobby . yours was made in Mexico , some are German .

ya alternators fit with these pumps .

[Broke67beetle]

Did parasitic draw test got 3.72

Does it matter if the green and blue wire are connected where the regulator was would that really make any difference

Installation guide says they should be connected.

[ashman40]

I'm gonna agree with mukluk. your VR or generator went bad (as evidenced by the GEN lamnp remaining ON while the key was OFF). This toasted the generator and/or VR. It may have also drained the battery. How old is your battery? Anything over 5yrs old and you are running on borrowed time. If the generator problem drained the battery it could have permanently damaged it. Batteries are only meant to be drained while cranking the engine for a few seconds. Once the engine is running the charging system quickly recharges the battery. Usually, deep discharging a battery is not good for it.

When you say the battery tests good, how did you test it. A state of charge test alone is not enough. You need a proper load test. Many digital battery testers do a simulated load test that works sometimes but may not accurately ID a battery that cannot carry the load. Take your battery to your FLAPS and see if they have the proper test equipment.

With your new alternator, start the engine and rev it a bit above idle and take a voltage reading at the battery terminals. You should see 13.8v ~ 14.5v at high idle. This confirms your charging system is working.


A parisitic drain is just something drawing current from your battery when it shouldn't (when the key is OFF). If you have a modern digital radio it will have a yellow wire that is connected to a battery constant power source. This wire is meant to keep power to the radio while the ignition is OFF so the memory and clock time is not lost. The amount of current draw from the radio is small. In the range of 100mA (0.1A) of less. Any current draw more than this will drain your battery if the car is left for more than a couple days.

If you remove the battery negative terminal and place a 12v test lamp between the end of the battery cable and the post of the battery and it lights up, it means current is flowing to/from the battery thru the test lamp. You have a prasitic leak.
If you have a Digital MM, set it to read <10A and put it in place of the 12v test lamp between the cable and battery post. Any current draw must pass thru the meter and you will see just how much current is being pulled from the battery. If it is more than 100mA (0.1A) you need to find the source. If less than this and you have a digital radio it may just be the radio. Disconnect the radio's yellow wire and see if the current drops to near zero. If there is little change it means something else is drawing current.
Leave the meter connected and move to the fuse box. Pull the fuses one at a time while you monitor the meter. When you pull a fuse and see the amp reading drop, you know there is somthing powered by that fuse which is pulling current while the key is OFF. A '67 Beetle should only have two fuses (#9 & #10) which are powered while the key is OFF. If removing either or both of these causes the current reading to drop to zero you know the problem is powered to one of these fuses.

If removing all the fuses makes no change to the current draw reading... disconnect the two wires DF and D+ from the alternator. Wrap them in a rag so they do not short to ground. Did the ampmeter readings change? At this point you have disconnected around 90% of devices. Next step would be to disconnect the ignition switch and the wires from the headlight switch.


Do some of the above a report back your findings. Good luck!
_________________
AshMan40
---------------------------
'67 Beetle #1 {project car that never made it to the road }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!}

[zerotofifty]

You should get a more correct aircleaner, one that has provision for crank case breathing, you got unplugged holes in the apron tin piece, which will allow hot air to be drawn into your cooling system and carb, not good.
Yes the regulator got fried, that is what caused the generator light to stay on.
You want a larger pulley? Which one? The lower pulley if larger will give faster fan speed, which can help cooling, the upper pulley if larger will reduce fan speed, not good!!!
_________________
Sorry About That Chief.

Give Peace a Chance.

Words to live by.

[Broke67beetle]

[Broke67beetle]

[Broke67beetle]

[mukluk]

[ashman40]

[Broke67beetle]

[wagen19]

Suggest to check 3 possible issues here:

a) new alternator, diodes are shot, if so, why?
b) your wiring has one or more shorts
c) your wiring is not original

to a: battery connected, engine and ignition switched off

If there goes current from B+ to D+ terminals of alternator, or from B+ to Ground inside of alternator, then the alternator diodes are shot.

1.) > disconnect wire D+ from alt. (gen lanp in speedo must go off if there is no short in D+ wire from alt. to lamp)

2.) > connect a test lamp at terminal D+ at alternator and on wire D+ (lamp on or off?) (>> if there comes voltage out of gen, when engine is off > diodes are shot)

3.) > disconnect wire D+ from alt. > connect test lamp on terminal D+ of altern.. and GROUND (lamp on or off?) or take voltmeter (if the light is on, there comes voltage through the alternator because diodes are shot)

4.) > connect an ampere meter on D+ of alternator and Ground (what current here?)

If the diodes of alternator are shot, voltage, current goes from B+ to D+ through the alternator, making the gen light in speedo on (when engine and ignition is switched off)

Over all, I´m afraid, some wires can have shorts, maybe only when engine is on and moves a bit (in area of chrome engine tin) that can have shot the some diodes inside of new alternator.

I´m thinking in that direction, because you have said, some days or some weeks after the new alternator was installed, everything was OK. (if I got it right)

[Broke67beetle]

No, the alternator never worked.
The battery died at the shop. Where the mechanic worked on it
He said, I needed a new battery.

The place where I got the battery charged and tested.
Said, battery is good, it doesn't want to replace

I installed the battery, it died overnight.


Tried a different battery
Connected Gen light.
Generator light stays on

Then I ran the parasitic draw tests.

[wagen19]