To convert or not to convert — Generator to Alternator

[Filthy Dub]

Hey everyone. I've read through a lot about doing a generator to alternator conversion on a 1600 motor and I'm a little hesitant still. So, I was hoping to get a little advice from people more experienced here.

For starters, let me briefly explain why I'd like to make the change. Awhile back, the bus died on me promptly after finishing a fuel up at a gas station. When I got home, the battery was reading like 10 volts on my ohmmeter. This is after purchasing a new battery maybe two or three months ago ... so something is wrong with the charging system, and I checked the brushes but they look almost new.

When I got her about six months ago, there was a mysterious flickering GEN light that would come and go (still happens randomly). Could the voltage regulator be to blame here? I'm about to say f*** it and buy an alternator conversion kit to rid myself of this infernal generator and it's problems, but I am trying to make wise decisions on a budget.

Thanks for helping out with this!
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1971 Westfalia Bay Window Bus

[SGKent]

1) did you replace the brushes ever? How about check them?

2) Was the flicker or glow only at night with the lights on and the Stereo turned up etc?

3) Are the headlights stock or are they high wattage aftermarket bulbs.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Filthy Dub]

[Randy in Maine]

Suggestion:

Before you do the deed, make sure that your battery to starter cables are clean, tight, and hopefully new.

Same with the battery to ground and the chassis ground strap.

[Tcash]

Did you sand the commutator before putting the new brushes in?
Tcash

[khalimadeath]

I had this same dilemma recently. Try and square away everything else before replacing the generator. I wanted to keep it OG, but a lot of people swap to alternators and don't have any issues.
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The United States Constitution
(c) 1787. All Rights Reserved


1970 Bus Westfalia
1964 Kombi

[telford dorr]

As you have a '71, you should have a 38 amp generator. To switch to an alternator, you'll have to change the following parts:

- fan backing plate tin, both inner and outer pieces (spacer ring between the two is the same)
- fan hub and appropriate shims and washers
- drive pulley
- alternator stand

All of these are different.

Now if you have a 30 amp generator (e.g. somebody swapped it already, usually as a part of an engine swap), then all you will likely need is the alternator stand.

In either case, you will have to fab up a new wiring harness which bypasses the generator regulator that you're also going to remove. For this, you'll need:

- a length of red #10 stranded wire
- a length of green #16 stranded wire
- one 5mm (1/4" is loose, but close) ring terminal, #10 wire size (for red wire at alternator)
- one 8mm (5/16" is close) ring terminal, #10 wire size (for red wire at starter)
- one 1/4" female spade terminal, #16 wire size (for green wire at alternator)
- one male 1/4" spade terminal, #16 wire size (for green wire to harness at old regulator)
- short length of heat shrink tubing to insulate the connection above
- appropriate crimp tools for above terminals

Sometimes the red wire comes from a stub wire on the battery cable. You can use this instead of the starter connection. You'll need a suitable butt-splice terminal, #10 wire size, to make the connection.
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'71 panel, now with FI
'Experience' is the ability to recognize a mistake when you're making it again - Franklin P. Jones
In theory, theory works in practice; in practice, it doesn't - William T. Harbaugh
When you're dead, you don't know you're dead. The pain is only felt by others.
Same thing happens when you're stupid. - Philippe Geluck
More VW electrical at http://telforddorr.com/ (available 9am to 9pm PST)

[Wildthings]

If you are only seeing 10v with the engine running then quite obviously the generator is doing little or nothing. Check your charging system wires (including grounds) carefully and run the tests on the generator and regulator given in the manual.

[Filthy Dub]

[Tcash]

Link

[Danwvw]

An alternator is a nice up-grade for the 1971 VW Bus. You will have charge at idle with an alternator! If you do upgrade to an alternator the 38' amp generators with their fan backing plate and pulley are valuable. I need the pulley for my Original and spare engine which still has the 38amp generator for my bus. I'd put an alternator on it though if I had one.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Filthy Dub]

How would I be able to tell if the voltage regulator is kaput?
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1971 Westfalia Bay Window Bus

[Danwvw]

Seriously, Change it for a new one as they are not expensive. The nuance details of testing are pretty involved. A voltage regulator for a VW bosch generator is doing two things. (well more than 2 but) It's Connecting generator D+(the generators + output) to B+ the + battery wire when charging and it intermittently connects the Generator F(field) wire to ground which makes the generator charge just right. I like the new Bosch Solid State Voltage regulators.
Just remember the wiring, the generator, the mechanical and regulator are a system and work together. I have found it's best to do everything when it comes to my charging system. Even the battery can cause problems with them. Mechanical voltage regulators some are pretty bad and won't last long, also if the battery is too big or drawing a lot of charge current it's rough on mechanical voltage regulators and generator brushes.
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[telford dorr]

[Tcash]

Hi Telford

[Tcash]

Another question, a variac is expensive.
What specifications would be needed?

Would one of these fit the bill?
https://www.amazon.com/Elenco-Variable-Voltage-Pow...entries*=0

https://www.amazon.com/Calrad-45-734-Regulated-Mul...wer+Supply

https://www.amazon.com/Precision-Variable-Supply-D...wer+Supply

Thanks again
Tcash

[chabanais]

I changed mine in 2000 no problems since.
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"I spud therefore I yam."

[telford dorr]

[telford dorr]

[Tcash]

Telford can we take this conversation over to here?
Charging System

Tcash