[responding to a very old thread]

I was having voltage problems in my 85 westy -- freeway driving with
AC and headlights on was causing battery to drain, not charge --
replaced the alternator but that really didn't fix it.

Finally took the advice and checked out the power wires from the
alternator -- sure enough, inside the wiring box they were totally
cooked.   Investigated some more, and realize just how crazy the
german engineering was.   Instead of putting in a single beefy wire
from the alternator to the starter, they put in two(!) on a single
crimp, then run these from the alternator in a spaghetti like path all
the way to the left side where they meet another wire, which then
reverses the course and ends up at the alternator.

Bently lists the 2 from the alternator as "2.5" which junction with
the one returning to the starter which is listed as "6.0".  If I'm
reading the diagram correctly, the entire electrical system passes
through this junction to the rest of the van.    I don't know what 2.5
and 6.0 represent  -- doesn't seem to be mm, mm squared, gague, or amps.

In any case, I'm replacing the two 2.5s with an 8 gauge and soldering
the connections, which should help a bit.

Anyone know if the existing "6.0" wire from the junction to the
starter is indeed what feeds the entire system?  Eyeballing it it
looks like about an 8 gauge as well.

I would also echo mark's recommendation that 85 and earlier owners
check the junction box -- it just takes a minute, no tools required.

On Aug 6, 2007, at 3:04 PM, Mark Drillock wrote:

> If I were you I would first examine very closely the 2 red power wires
> from the alternator and also follow them to their other ends. I have
> seen more of these cooked than you would think. They are often
> cooked at
> the ends hidden inside the engine compartment wiring box. VW increased
> the current capacity of this circuit by 250% in later years and that
> is
> what I would do on yours. Run a new 8 gauge wire from the alternator
> to
> the starter motor, using soldered on wire ends made for 8 gauge wire
> and
> 5/16 bolt hole. This will likely cure most of your problem but if you
> measure the voltages at the starter motor lug first you will know how
> much of the drop is there. Test unloaded and loaded, as before.
> [...]
> Mark