6v regulator adjustment

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Jim White
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6v regulator adjustment

#1 Post by Jim White » Mon Aug 05, 2019 10:07 pm

I've got a new, well new to me, Bosch 3 post, 6v regulator. I'm only measuring battery voltage (6.25) at 2,000-3,000 rpm and the generator light stays on and flutters or flickers a bit.

With the field wire grounded, I'm measuring 10.4 volts from the generator which has just been rebuilt. The car has a new optima battery.

The initial gap on the voltage regulating relay is only .020" instead of .032 " - .051". My question is, do I start by adjusting the contact point rest post to get the initial gap into spec, or just go to the blue spring rest post adjustment ?


Many thanks!

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Mike Wilson
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Re: 6v regulator adjustment

#2 Post by Mike Wilson » Mon Aug 05, 2019 11:38 pm

From Joe Leoni's book, "356 Electrics" which is an invaluable resource:

1. Preliminary
Factory recommendations for voltage is 7.1 to 7.5 volts.
When measured at the generator, a good value is 7.3 volts.
2. Adjusting
Remove the B+ wire from the regulator. It is hot, better tape it off.
With the engine warm and running about 2500+ rpm, measure the generator's voltage at D+ on the regulator.
There are no electrical loads on the generator at this time.
All other electric loads will be from the battery, not the generator.

Tap the rest post down, to raise the voltage, or up, to lower the voltage if it is too high.
Increasing the rest gap will increase the voltage.

Voltage changes of not more than 1/2 volt can be adjusted with this method.

Mike
Last edited by Mike Wilson on Tue Aug 06, 2019 11:59 am, edited 1 time in total.
Mike Wilson
Lomita, CA
'63 B coupe

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Ron LaDow
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Re: 6v regulator adjustment

#3 Post by Ron LaDow » Tue Aug 06, 2019 12:17 am

Jim White wrote:
Mon Aug 05, 2019 10:07 pm
I've got a new, well new to me, Bosch 3 post, 6v regulator. I'm only measuring battery voltage (6.25) at 2,000-3,000 rpm and the generator light stays on and flutters or flickers a bit. .."
You've got able assistance from Mike; have at it,
But from the rabble (including MIke; he was just more interested in your problem), welcome. 2 drink minimum, but worth it.
Ron LaDow
www.precisionmatters.biz

Jim White
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Re: 6v regulator adjustment

#4 Post by Jim White » Tue Aug 06, 2019 8:29 am

Thanks Mike and thanks Ron for the welcome. From that 1/2 volt adjustment limit I know I need to adjust the point rest gap first.

I was a member about 25 years ago for a few years.Have the same car, just lost a quarter of a century and raised two kids.

I'll keep looking for Joe's book and will be back with current limiting questions when I get the voltage up.

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Mike Wilson
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Re: 6v regulator adjustment

#5 Post by Mike Wilson » Tue Aug 06, 2019 10:53 am

As always, we're glad to be of help and...welcome back!

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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Mike Wilson
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Re: 6v regulator adjustment

#6 Post by Mike Wilson » Tue Aug 06, 2019 11:42 am

I'm pretty certain Joe's book is available through Bill Block, one of our trusted vendors. He also has many other 356-related books that are valuable sources of information.

Mike
Mike Wilson
Lomita, CA
'63 B coupe

Jim White
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Re: 6v regulator adjustment

#7 Post by Jim White » Wed Aug 07, 2019 8:06 pm

I opened the point rest gap from.020 to.032 and the voltage went from 6.25 to about 7.15 (oscillating between 6.9 and 7.4). I haven't touched the blue leaf rest post up top.

The closed position gap was, and still is .020. I'm leary of closing it down to.008 for fear of it changing the open gap or voltage. I've order Joe's book as I'd still like to adjust the current portion and I've got a couple lighting issues (like dim 6v headlights lol).

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Mike Wilson
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Re: 6v regulator adjustment

#8 Post by Mike Wilson » Wed Aug 07, 2019 8:31 pm

Congrats on your progress!

Mike
Mike Wilson
Lomita, CA
'63 B coupe

Jim White
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Re: 6v regulator adjustment

#9 Post by Jim White » Thu Aug 08, 2019 10:59 am

Thanks. You wouldn't happen to know the air, or static gap for the current regulator would you? It's not opening and closing like the voltage regulator or cut out switch.

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Mike Wilson
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Re: 6v regulator adjustment

#10 Post by Mike Wilson » Thu Aug 08, 2019 11:18 am

I'm sorry I don't, Jim. The info I posted was the only I found in Joe's book. However, I have had several of the Bosch relays restored by him and he included info sheets with them so maybe the info is there. I'll check my stash. Also, one if our more knowledgeable members probably knows.

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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Mike Wilson
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Re: 6v regulator adjustment

#11 Post by Mike Wilson » Thu Aug 08, 2019 1:17 pm

Nothing in the info Joe sent me but if you send me a PM with your email address, I did find a schematic I can send to you.

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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