Date:         Wed, 17 Apr 1996 15:31:48 -0400 (EDT)
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         "H. Steven Dolan" <dworkin@mtolympus.ari.net>
Subject:      Breadloaf Rear Wiring Harness replacement procedure (long)

John,

I just did a wiring harness swap as part of the engine swap I have been
reporting. It was very easy, took about 2 hours.  Following is the
procedure for your use if you decide to do it.

Rear Wiring Harness Replacement Procedure

The tools you need are screwdriver, needle-nose pliers, string, tape,
*BENTLEY MANUAL*, and VOM.

Start at the front, under the dash.

Unplugging at the front, you will wind up with one 8-gang plug and 5-6
loose wires.  Draw yourself a diagram of the position of the wires in the
plug and remove the wires from the plastic. I found that I could slide a
small flat-blade screwdriver in from the front and release the retainer on
each spade and withdraw it easily.  Tape all the wires together, add the
string to the bundle and start feeding it backward.

Feed it Back to the Starter

There are a series of metal fold-overs that need to be released as you
work your way back from the front, over the axle beam to where the harness
enters a tube that carries it to the back of the bus.  WEAR SAFETY
*GOGGLES* under there. The amount of rust/mud that will fall in your face
is incredible.  Beyond the tube, there are a few more fold-overs over the
rear axle, then the fun begins.

Disconnect the starter and Gas Guage

Before you can feed the harness into the engine compartment, there are two
branches from the main harness, one (3 Wires) to the starter, a second
(one wire) to the fuel guage.  The starter is easy, just remove the nut
and unclip the wires. The fuel guage is trickier.  I had the gas tank out,
so I just unplugged it and pulled it thru, but if you don't want to take
the fuel tank access panel off, (8 screws {3 on each side of the panel in
the engine compartment, one on each side of the tranny from underneath}),
I believe there may be enough slack to work an intermediate connector
through the grommet and release it there. At that point tape the
starter/gas guage branch firmly to the main harness, pointing the free
ends toward the rear of the car so it feeds smoothly.  The harness can
then be pulled through the firewall. Store this monster on the shelf over
the engine.

Swap plugs at the back

Lay the new harness behind the vehicle and start swapping plugs.  There
are 3 major branches on the harness.  I did them in the following order:

1) Fan branch runs to the fan at the top of the compartment and one wire
to the coil.

2) Light branch runs to the tail lights and licence light.

3) Reverse light branch (plus electric fuel pump and FI power after '74)
is a continuation of the light branch that goes back under the car
through a hole on the drivers side firewall.

I was careful to match wire color to wire color and had no problem.
After you have completed the swap, remove the old harness,

Tie the string to the new harness and work it forward, reconnecting the
starter and gas guage as you go.

When you reach the front use the diagram you made at the beginning to
rewire the plug, and the bentley wiring diagram to locate the rest of the
wires. Two things to note are, first, that while most of the wires go to
the fuse block, not all do.  The turn signal wire connections are of the
block on 3-way connectors hanging loose. Secondly, some of the fuses share
a common bus.  The Bentley manual shows the main power wire (red/white
stripe) connected to the base of fuse 9, but when I got there, there was
already a wire on that terminal. close examination showed that the bases
of fuses 8 & 9 share a common bus, and the lug at the base of fuse 8 was
vacant, but shiny. On it went there and worked fine.


Having typed all this, however, I believe that your problems are probably
corrosion related, and that a new harness would be overkill (if you can
get a new harness).  Try just going over the whole system with a piece of
extra fine sandpaper, brighten everything in sight, replace any broken or
loose lugs, and I'll bet everything will work just fine.

                           H Steven Dolan
                           Alexandria, VA


On Wed, 17 Apr 1996, John Breitenbach wrote:

>
> Does anyone know where
> I can get a copy of the schematics for a '74 bus?  I've given
> some thought to running a whole new harness from front to back,
> anyone ever attempt this?