[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

Re: [T3] 12V conversion


The following has been posted here before.  You will also want to find
the comprehensive thread about alternators:

Here are the steps to change your type 3 from 6 volts to 12 volts:

Change the cast aluminum fan housing, and install the larger 12v
generator.  It is possible to get a 12v generator the same size as a 6v,

so that you do not have to change the fan housing.  Try Bill & Steve.

Change the coil.

Change the chokes.

Change the idle cut-off solenoids.

Change the flywheel.  Use an automatic transmission starter so that you
do not have to change the starter shaft bushing. There was a flywheel
hub
design change, as the older crank shaft end had a bulge.  The flywheel
has a
step cut into it to clear this bulge.  It is probably easier to have a
step machined
into the flywheel hub than to disassemble the engine to have the crank
shaft end
dressed.  Finding the correct flywheel is best.  Finding the old style
hub flywheel with a removable ring gear (and the correct ring gear to go

on it) is next best, but harder.  A 6v bendix gear in a 12v starter is
rare, but I suppose that you could disassemble a 6v starter, and have
the gear welded and redrilled for mounting in a 12v starter.  Or don't
change the
flywheel and run your 6v starter until it burns up.

Change the voltage regulator.

Change the battery.  Your battery cover will not fit anymore.

Change the windshield wiper motor.  Or install a resistor to cut the
voltage.  Or run your wipers really fast until you burn them up.

Change the fuel gage in the dash.  No need to change the sender in the
tank.

Change the clock.  Or don't worry about it because it won't run for ever

anyway.

Do something with the radio.

If you have an electronic tachometer, you will have to change it.

Change the headlight relay.

Change the turn signal relay.

If you have a horn relay, change that.  Change the horns.

Change every light bulb, everywhere.

That ought to about do it.

Does anybody get the idea that a 6v to 12v conversion is quite a bit of
work,
not all of it simple?

The easiest thing to do if your 6v electrical system is getting tired,
is to put a 6v horn relay (from a Karmann Ghia) in the solenoid circut,
so that your soleniod can get a full 6 volts.  You can do a similar
trick in the coil circut.  If you think your wiring is getting tired,
try measuring the voltage at the coil.  When internal resistance drops
the voltage to less than about 5.5 volts, you will have trouble starting

the car from weak spark.  A similar test at the solenoid will tell you
that you will have trouble getting the starter to work consistantly.
You can also replace the stock battery cable, which is about 4 gage (I
think), with a heavier 0 gage cable to be certain that there is no
voltage loss going to the starter.  If you change the positive battery
cable, you might also want to secure the starter ground, by putting a
longer bolt through the body where the battery is grounded now.  Under
the car, run a cable from the longer bolt to one of the starter mounting

bolts.  This gives you a more direct ground, again to avoid voltage drop

at the starter.  This 6v clean up stuff is a lot easier than a 12v
conversion, and lets you keep your car stock because no body can see
your modifications.  Of course, a 12 volt system is not so subject to
tired harness disease, and lets you use a modern radio.


Tim Dapper


Cale Haack wrote:

> i'm planning on converting my 66' Notchback to 12v with an alternator
> and i was just wondering what parts i would need to do this.
> i've heard that you need a voltage drop for your wiper motor too.
>
> -------------------------------------------------------------------
> List info at http://www.vwtype3.org/list or mailto:help@vwtype3.org




[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]