Conversion 6 volt to 12 Volt for backup engine

Mel P.

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Jun 10, 2006, 11:15:02 AM6/10/06

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I have a 1965, 6 volt engine. I want to rebuild it and use it as a spare
for my 12 V KG & Bug. Besides the flywheel and generator/alt, what else
would I need to change?
--
Mel P.

Speedy Jim

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Jun 10, 2006, 12:19:28 PM6/10/06

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Mel P. wrote:

Nope. Can't put an ordinary 12V flywheel on that 6V crank.
There may be some crossover flywheels but they are scarcer
than hens' teeth.

Change:
Coil
Carb solenoid and choke.
Oil stand (to accept new 12V whatever).
Pressure plate (assuming your 12V KG uses later style TO bearing).

To get around the flywheel issue, keep the 6V one and install
6V starter (the teeth must match) AND change the pinion bush in the
bellhousing. Run 6V starter on 12V.

See the 6V/12V article on my web site for more info.

Speedy Jim
http://www.nls.net/mp/volks/

dave AKA vwdoc1

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Jun 10, 2006, 9:03:36 PM6/10/06

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IIRC, and I don't work on that many air cooled VWs anymore since they are
really scarce here nowadays. :-(
Some of the 6V Busses had a 200mm flywheel AFAIK, and yes I believe that
they are scarce. I believe that those flywheels had the correct amount of
teeth for the starter.

Are you sure the 12V flywheel won't fit on the 1965 6V crank? Maybe on the
1966 Crank (different engine though)?
WHY? Is it because the 6V flywheel might use a gasket and the 12V uses an
O-Ring to seal with the crank.

The top of the carb may need to be changed due to the 12V choke being
larger.

If $$$ is no object the early Porsche 912s and late 356s had a smaller
diameter generator that should fit on the VW 6V generator stand.

Old but still trying to learn! <g>
later,
dave
(One out of many daves)

"Speedy Jim" <vo...@nls.net> wrote in message
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Speedy Jim

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Jun 10, 2006, 9:32:22 PM6/10/06

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dave AKA vwdoc1 wrote:

> IIRC, and I don't work on that many air cooled VWs anymore since they are
> really scarce here nowadays. :-(
> Some of the 6V Busses had a 200mm flywheel AFAIK, and yes I believe that
> they are scarce. I believe that those flywheels had the correct amount of
> teeth for the starter.
>
> Are you sure the 12V flywheel won't fit on the 1965 6V crank? Maybe on the
> 1966 Crank (different engine though)?
> WHY? Is it because the 6V flywheel might use a gasket and the 12V uses an
> O-Ring to seal with the crank.

<SNIP>

Some '66 cranks will accept the 12V flywheel.
But not '65. It's not the gasket but the shape of the
crank end; one has a step, the other not (over-simplified).

OTOH, the 6V flywheel *will* fit on the 12V cranks! <bg>

Jim

dave AKA vwdoc1

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Jun 11, 2006, 11:01:02 PM6/11/06

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> <SNIP>
>
> Some '66 cranks will accept the 12V flywheel.
> But not '65. It's not the gasket but the shape of the
> crank end; one has a step, the other not (over-simplified).
>
> OTOH, the 6V flywheel *will* fit on the 12V cranks! <bg>
>
> Jim

lol ok
thanks Jim

WSJOHNSON

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Feb 28, 2009, 2:10:13 PM2/28/09

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Hi Mel,

When you convert your VW form 6 V to 12 V you can replace your starter
with the BOSCH HYBRID 6/12. This remanufactured starter has all the
mechanical dimensions of a 6 V starter with internal components modified
to operate on 12 V.

The BOSCH HYBRID 6/12 starter mounts in 6 volt transmission with a 6 V
flywheel and 6 V bushing. No modifications are necessary. You
don’t need to spend the time and money to remove the engine,
replace flywheel, replace pinion bushing or grind the bell housing.
Using a stock 6 volt starter in a 12 volt conversion will damage your
flywheel and starter teeth. Don’t risk sudden starter failure and
getting stranded with a burned out 6 volt starter. This is a quality
remanufactured BOSCH starter.

The HYBRID 6/12 will replace 6 V starters on Beetle 1946-1966, Ghia
1956-1966, Bus 1950-66, TYPE 3 1962-1966 Starter Number: SR11X

--
WSJOHNSON
Message Origin: TRAVEL.com

KWW

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Mar 1, 2009, 6:25:52 PM3/1/09

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On the other hand, you could just use a 6V starter and get really quick
starts! Just don't hold the starter on too long or it will burn out.
(and make sure you have a good selinoid.

Jan Andersson

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Mar 1, 2009, 6:56:51 PM3/1/09

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replace the 6V solenoid with a 12V unit, leave the rest of the starter 6V?

P.J.Berg

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Mar 1, 2009, 8:20:55 PM3/1/09

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I ran 12V on a 6V starter for years, no problem what so ever.
That being said, I do not claim it is the correct way to do it, but it works..

The only problem I encountered during all those years was the windshield wiper motor giving up on me.
Turned out to be one of the soldering points on the rotating assembly let go.

And the fact I nearly froze to death running a -56 T1 without any heat what so ever during -20C for 3 hours plus, traveling to and from the Military base where I was stationed.

My knees still disapproves of the cold, ah, being 18 again would be nice.. :-]

J.

--
Using Opera's revolutionary e-mail client: http://www.opera.com/mail/

Bugger

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Mar 13, 2009, 9:30:59 PM3/13/09

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I have tried putting a 12v solenoid on a 6v starter. The solenoid did fit
but the stroke length was different. The contacts would never make up when
the solenoid was activated so the starter would not spin. Is there some kind
of modification that needs to be made so that the 12v solenoid will work?
Dave P

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