Generator, Regulator and Battery Wiring

[Dubskii]

I bought a bus this past week and was told it had some charging issues (idiot light is on, bus runs though!). It is a 12v system with a generator. I changed the brushes and started her back up and the light was still on. I went back to look at the engine and noticed there is no direct connection from the regulator to the battery. Is this correct?

Pic of the Generator wiring

Pic of the Regulator wiring

The wiring on the right of the regulator is from the D+ and DF terminals as well as the ground on the generator. The thick red wire on the left is from the wiring harness (not sure what that is connected to) and the thin wire behind that is to the idiot light. Ideas as to this red wire?

Pic of the Regulator to Battery

This pic shows there is no connection from the regulator to the battery.

Questions:

1. Should there be a direct connection between the regulator and battery? 2. Is it possible that this connection occurs at the starter?
3. If no to Question 2, should I connect a wire to the battery from to the regulator terminal just above the thick red wire on the left?
4. If yes to Question 3, what gauge should this wire be?

Also, I have not tested volts yet. Not really sure how to do that.

Thanks for any help.
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69 Sunroof Deluxe - Montana Red/Cloud White (Sold)
57 Kombi - Dove Blue http://www.thesamba.com/vw/forum/viewtopic.php?t=648240
WTB Early Dove Blue Bus Driver's Side Door
WTB Joe Heishman VW Arlington, VA License Plate Frame or Other Memorabilia

[joe cool]

connection is made at starter motor
get a wiring diagram before you damage something expensive
(also make sure you are sending 12v from generator idiot light to voltage regulator, good chance this is why your warning light is on)

[Dubskii]

I have seen this diagram from Speedy Jim's site which shows the hook up I have but also a wire directly to the battery from the regulator. If the connection is made at the starter then that is good.

My volt meter on my dash reads 12v when I start the motor. Is that 12v showing from the generator, regulator or battery?

Next, I will test the battery both with engine off and engine on.

Is it possible everything is fine and the light will just be on?
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69 Sunroof Deluxe - Montana Red/Cloud White (Sold)
57 Kombi - Dove Blue http://www.thesamba.com/vw/forum/viewtopic.php?t=648240
WTB Early Dove Blue Bus Driver's Side Door
WTB Joe Heishman VW Arlington, VA License Plate Frame or Other Memorabilia

[srfndoc]

B+ goes to the positive terminal of your battery.

61 goes to the generator light in your speedo.

At least that's how a stock 12v system is setup:

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RPM=(MPH*336* (R&P*4th*1.26))/Tire Diameter in inches

[Eric&Barb]

Not good that the red light is on all the time with engine running. Not only probably bad for the battery, but bad for the engine when (not IF) the fan belt breaks. Then little to no cooling air goes over the engine to keep it cool and in a few minutes or sooner you will need an engine rebuild. With idiot light working properly you know to pull over ASAP and fix/replace the belt.

Get proper positive battery cable grommet in that front fire wall and avoid the cable getting cut thru the insulation and causing a wiring fire.

Post more images of the engine, so all here can point out any more future surprises you may want to avoid.
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In Stereo, Where Available!

[telford dorr]

Simplified wiring:

Note: 'to battery" = to starter.

To test:

1) With the ignition key ON, unplug blue wire going to the regulator '61' terminal. The GEN lamp should not light. The GEN lamp should light when the blue wire is grounded to the regulator case. Reconnect after testing.

2) With the engine running at a fast idle, connect a voltmeter between the generator D+ terminal (+) and ground (-). Mind the spinning fan belt. You should read between 13.8 and 14.4 volts.

3) Connect the voltmeter between the regulator terminal 61 and ground. You should measure the same 13.8 to 14.4 volts.

4) Measure from the regulator Df terminal to ground. It should be less than battery voltage by a few volts. Under slow speed operation, it could reach 0 volts. It will fluctuate with engine speed.
_________________
'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)

[Dubskii]

Excellent info. This morning I tested the battery with the engine off and it read 12.5v. If I run the engine and test the battery it should read 13-14v, correct? If so, I know my battery, regulator and generator setup is working properly. Stay tuned.

Also, I will get a firewall grommet.
_________________
69 Sunroof Deluxe - Montana Red/Cloud White (Sold)
57 Kombi - Dove Blue http://www.thesamba.com/vw/forum/viewtopic.php?t=648240
WTB Early Dove Blue Bus Driver's Side Door
WTB Joe Heishman VW Arlington, VA License Plate Frame or Other Memorabilia

[Eric&Barb]

Should read about 13 volts IF the battery needs a bit of charging up and the engine RPM is a bit higher than idle speed.
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In Stereo, Where Available!

[guatebus]

Doesn't the regulator ground through the body?

It appears to be just sitting in the engine compartment and maybe there's not a good ground connection being made.
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'64 standard microbus
'69 deluxe microbus

[Eric&Barb]

If you look carefully in the second image there is a large Phillips screw thru one foot/mount.
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In Stereo, Where Available!

[telford dorr]

That's what the brown wire in the generator - regulator harness is supposed to be for. Although it's a but strange, as the regulator is also grounded to the body. So there seems to be multiple ground paths for the regulator. I suppose the brown wire is supposed to guarantee that the regulator ground is the same as the generator ground. Problem is, if the trannie ground strap is bad or missing, the generator is going to try to use that tiny wire as a ground return, most likely with less than stellar results.
_________________
'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)

[xcoldgrimjimx]

[telford dorr]

The brown wire is supposed to make sure that the voltage regulator is referenced to the generator, and thus the voltage seen by the regulator (D+ to D-) is what the generator is putting out. This way, the regulated voltage is what it should be. Without the brown wire, there could be unknown voltage drops between the engine and the regulator, resulting in a confused regulator and an unknown generator output voltage.

Now with that said, because the regulator is screwed to the body (and thus grounding to it), any voltage drops (like from a bad trannie ground strap) could still (theoretically) override the brown wire a bit. [Back in the 6 volt split window days, the regulator was physically mounted to the generator, rendering this possibility moot.]
_________________
'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)

[ryans65]

I put the wiring works harness in my 65 over three years ago, the body guy removed it and I've got it all back in now but cannot for the life of me figure out where the B+ wire from the generator to the battery + is. Anyone out there that has done one of these recently know if that wire was in the wiring works loom? It is not mentioned on the page that details the separate small single wire sections like the headlamp grounds etc. so I know it wasnt something I've overlooked or was it? Looks like it is supposed to be a 6mm wire so can't be easily mistaken for anything else.

[ryans65]

[Eric&Barb]

For 1500cc factory supplied VW buses:

https://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=311971225C
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In Stereo, Where Available!

[ryans65]

Awesome, thank you!!! I'll add that to my next (hopefully last) large WW order.

[Danwvw]

Found mine in the trunk!
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1960 Beetle And 1679cc DP W-100 & Dual Zeniths!

[Eric&Barb]

[ryans65]

ground cable is on the list as well, got a lot of little bits to get me to the finish line then a pile of stuff on the bed i've bought twice, bought wrong etc. ha!

thanks again