Final wiring and testing

First let me say that I don't have a wiring diagram to post. There's a good reason too: I didn't want to spend 2-3 hours doing a nice version I could show here, only to find out I had issues. Turns out I was right, but I'll explain later.

Anyhow, I've already shown how I made my little spacepod control module for the dashboard. It was finally time to wire in my controller, gauges, switches and indicator lights:


Left to right:
Green switch: Switch to veggie oil
Yellow light: Comes on when you've switched to veggie oil, but the car is still cold. At 50*C, the temperature switch allows the switchover to vegetable oil
Green light: Comes on when switched to vegetable oil
Red light: Stays on during the timed "purge" cycle
Vacuum gauge: Measure vacuum before filters. If vacuum climbs, filters are plugging
Temperature gauge: Monitors fuel temperature
Yellow switch: Controls direction of vegetable oil return: Either back into the fuel "loop" or back to veggie tank.

Here's the mess 'o wires:


Before cleaning everything up, I tested all the functions:


What I found was that my yellow indicator light was triggering a relay in the controller that activates the return valve. That meant that if I switched to veggie oil while the car was still warming up and the yellow light was on, it would actually trigger the return valve, sending diesel back to the vegetable oil tank. No good.

I ended up rewiring the indicator light to get its ground from the Vegtherm, then it worked. I'll post a wiring diagram after it's worked fine for 2 weeks... I've already made 3 changes.

Anyway, once that was sorted out, I tried to tidy up the wires a bit, so they wouldn't snag too easily when I pull it in & out of the dash... something I have to do in order to adjust the purge timer.


Then I slid it into the dash:


As for wiring, here's where I got my 12V "illumination" feed from the light switch. It's grey & violet. There are two bundles of wires going into the light switch, this one came from the bundle on the right. Unfortunately, this one feeds a full 12v, not the "dimmed" voltage... so the gauges are on BRIGHT. I haven't been able to find a "dimmed" illumination feed... if anyone has more luck, let me know.


Here are the wires going to the switching valves, Vegtherm, temperature gauge sender and VegSensor. All wires are easily disconnected in case the intake manifold ever needs to come off (i.e. once a year for glow plug preventative maintenance)


Here are the wires going back to the Vegtherm relay & circuit breaker, then back behind the brake booster, where they pass under the dash (bottom of page).


Anyway, the fussy folks out there (hi dad!) will notice that the wires aren't "tidied up" or sheathed yet. There's a good reason: There's no use wrapping everything up until it's all been working perfectly for a couple weeks. No use spending a whole lot of time making it pretty, if there's still a chance it has to come apart again.

Same thing with the fuel & coolant lines under the hood. They'll remain uninsulated for at least a week. If they are leak-free after that, they'll get wrapped up tight.

In the meantime, everything is secure.

So, we should be ready to flip the switch tomorrow!