Switcheroo

Today, I got a couple of hours, so, with a steady rain and 35* work conditions, I decided to focus on something inside the bus rather than underneath it. I had a choice, either the fan control or the coolant flow valve control. I decided on the fans. I'll go into that today.

Wire Bundle
I had already bought the wire, so I figured I had all the parts for doing the fan controls. Using 14-gauge wire, I created a 3-wire cable bundle. I chose yellow-white-blue rather than the usual red/green/black combination, simply to be different. Like the wire bundle I ran for the ignition controls (link), I ran the cable through the large rear cabinet, along the outside of the low cabinet and stove/sink unit to the spare tire hole. I had drilled a small hole in the partition wall for the ignition cable, but I needed a new one for this new bundle. The wires then followed the same path along the edge of the door opening under the carpet to the A-pillar (next to the clutch pedal). The wires routed behind the fusebox and over the steering wheel support to the series of switches to the right of the ignition.

Switch a switch
My old 1972 dash controls were extremely simply by modern standards. To the right are 3 switches: dome light, wipers and hazard (left to right). The dome light switch doesn't actually do anything anymore. My dome is wired directly to the accessory battery fuse-block now, so this switch was useless. I chose to remove this switch and re-use the dash-hole for the fan control. After looking through both the Bentley and the Idiot's book, I was unable to find printed instructions for removing a switch. I went digging through my old parts and found a few old switches. By examining their construction, you can tell that the hand-knob just twists off (lefty-loosey). This leaves the stem and a round threaded silver collar sticking out of the switch body. The round silver collar also hand-twists off (lefty-loosey again), leaving a gray female collar attached to the switch body. By applying this learning, I was able to remove the dome light switch. If you have a switch that is correct for your model year, the install is the reverse of that removal. My fan switch, though, is from a Vanagon, so I had some more work to do.

Retrofitting a Switch
The Vanagon switch is much more modern. The switch housing clicks into the outer skin and the outer skin clicks into the dash. The outer skin of the fan housing does not integrate with an old bus, so I set it aside, leaving me with the switch body and the hand-knob. Unlike the older knobs, this one just slides into place and remains in place through friction. This may be useful later if I can figure out a way of re-using some of the outer skin. Anyway, to get the switch housing to hold in place like an old-style switch, you need to re-use the threaded silver collar. Since the new-style switch doesn't have anything to thread into, things get interesting. I went through my spare switches and found one that didn't work (tested with multi-meter) consistently. I cut the gray female collar off of the bad switch, filed off the rough edges and crazy-glued it to the Vanagon fan switch. I love how one sentence can summarize 30 minutes of effort and who-knows-how-much problem-solving time. With the gray collar firmly in place, I was able to wire up the switch and install it.

Wire Color Notes
As I mentioned above, I chose to use yellow / white / blue as my wire color choices for the fan controls. I'm sure a time will come when I'll have to diagnose a problem, so, for future reference, the yellow is for "low", the white is for "middle" and the blue is for "high". I striped and wired up connectors for the bundle. I tied them into the fan switch following the pattern I just mentioned. The switch still needed a power source, though so I located the B+ source for the original blower fan signal.

Once wired, the switch settled into the old dome light hole, and hand-tightened in. From the picture, it doesn't look straight-stock, but it does look pretty good. If I get all trailer-queen anal about it, I could probably find a hand-knob with a fan icon on it and figure out a way to get it to interface with the switch body. I just want it running and not have things looking half-assed or half-finished. This meets that bill. That's all I have for today. Over Thanksgiving, I'll get the heat box in, and I'll post on some changes / modifications I needed to do to get it run-ready.

Pictures:
top - view from the ground when I slide out from under the bus.
middle left - Vanagon switch modified with gray and silver collars.
middle right- 2 dome light switches, one after the gray collar was removed.
bottom - the fan switch installed next to the stock wiper control knob.