12v conversion

RyanB · Post by **RyanB** » Tue Sep 26, 2006 3:01 pm

So I recently got a 66 Beetle (baja) and the motor I am putting in to it has an Alternator. I know that to run 12v in a 6v system I need to put in a convertor for the Windshield Wipers. However what about everything else? Lights should all work, just be brighter right? Is there anything else that I should worry about besides the wipers? Can the starter motor handle 12v? Cant think of anything else...

Thanks.

~RyanB

Speedy Jim · Post by **Speedy Jim** » Tue Sep 26, 2006 3:17 pm

Yes, you can run the starter on 12V (helpful though to
replace the solenoid with a 12V unit).

Read the article on my web site:
"6V/12V Conversion checklist"

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

Post by **Marc** » Tue Sep 26, 2006 3:19 pm

http://www.shoptalkforums.com/viewtopic.php?t=70327

You'll need to change all the bulbs - they'll be bright while they last but 8 volts is about all a "6V" filament can handle for long.

Assuming the new alternator-equipped engine has a 12V (130-tooth) flywheel, you'll need a matching starter and the bellhousing has to be clearanced slightly in five spots for the larger-diameter 'wheel. Also it must use an early-style clutch cover with center thrust ring to be compatible with the `66 transmission's cross-shaft/release bearing setup.
If you use a "normal" (SR15X) starter the bushing in the bellhousing will have to be replaced with a special thick-wall adapter bushing; an AutoStick (SR17X) starter is self-supporting so you can skip that step if you use one of those.

If the wiring's basically healthy it (and the switches) should be fine on 12V (it takes only half the current to deliver the same power at the higher voltage). You may even be able to get away with keeping the 6V flasher relay, many people have run them on 12V for years without burning out. If it does fail, you can forego the 4-way feature and use a simple 12V flasher, switch to a `67/`68 flasher relay, or rewire the hazard system to the `69-up style that uses a complex switch rather than the compound relay.

Speedy Jim · Post by **Speedy Jim** » Tue Sep 26, 2006 4:06 pm

Good catch, Marc!

I was asleep at the switch

Ryan, delete all I said about the starter...

RyanB · Post by **RyanB** » Wed Sep 27, 2006 9:51 am

Thanks guys! Great info!

Berg Fan · Post by **Berg Fan** » Fri May 04, 2007 1:49 am

Hey Marc, when you say you must use the early clutch cover, do you mean an early 12v 200mm one as a 180mm wouldnt fit would it ?

Post by **Marc** » Fri May 04, 2007 8:27 am

****sigh****
One more time, there is no direct correlation between clutch diameter and flywheel tooth count.

1200/1300cc engines came with 180mm clutches, 1500/1600cc engines came with 200mm clutches; in the US market bugs all got 1500s in 1967, the same year all our cars went 12V. In this one case the term "12v 200mm" is almost accurate...until you remember the pre`67 6V buses and Type IIIs that also had 1500s and 200mm clutches.

Of course I'm referring to the pre`71 200mm clutch cover (311 141 025E) in this instance because it's a fairly safe assumption that if RyanB has a 130-tooth flywheel it takes a 200mm clutch. There are 130-tooth 'wheels which take 180mm clutches - but none came on any car delivered in the US.

Berg Fan · Post by **Berg Fan** » Sat May 05, 2007 1:48 am

Sorry,Iam relitively new to VWs on this side of the planet(NewZealand). I had the 12v 130 tooth 180mm clutch setup on a 1300cc '69 car.

aussiebug · Post by **aussiebug** » Sun May 06, 2007 4:48 am

Re the wipers - there's a neat little circuit on my site which runs the 6v wipers on 12v with no excess heat (as happens when using a resistor).

Just four components from Tandy/Radio Shack etc

http://www.vw-resource.com/wiper1.html

John Denhart · Post by **John Denhart** » Wed May 09, 2007 10:40 am

Almost 30 years ago I converted my 65 6v bug to 12v. I used Ford Cortina generator components in the Bosch housing then just changed bulbs, flasher and dropped the wiper motor to 8v using a resistor from a forklift. The wipers worked great ( as liitle as we use them here in San Diego ) with out energizing. I just let the 6v starter rip as I used it sparingly.

Berg Fan · Post by **Berg Fan** » Thu May 10, 2007 12:31 am

Can you remember exactly how you converted the generater, sounds very interesting. Something else I was told you have to do is the fuel gauge and sender unit but the horn seems ok with 12v going thru it !

Post by **Marc** » Thu May 10, 2007 4:13 am

The stock fuel gauge on a pre`68 Beetle is mechanical and unaffected by the conversion. If you have an optional electric gauge and it's the thermal type, it'll have to be replaced..but if it's the balance coil type as was used in 6V 'Ghias and buses it should be able to handle the higher voltage.
A 6V horn might burn out after a few minutes' continuous operation on 12V, but it's so horrendously loud that you'll only be using it for seconds.