Plumbing
From Bytesmiths
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Contents |
Fuel System Plumbing
Engine Coolant
Engine coolant is used to heat the vegoil so it will approach the viscosity of diesel fuel. I put a "T" in the coolant line going to the cab heater, and there is another "T" in the return line.
I pulled the hose barb from the engine, and discovered it had a restriction in it, so I replaced it with a full-flow hose barb. Someday, I want to put adjustable shutters in front of the radiator to help regulate engine heat -- the Cummins 4BT is so efficient that it can be hard to get much heat out of it when air temperatures drop below 10° Centigrade or so!
Coolant heat goes from here to the driver's side, into the Vormax filter, then into the left vegoil tank. The coolant outlet of the left tank is tightly bundled with the fuel lines going to the right tank and the fill/recirculate valve, and the whole bundle covered with insulation. This so-called "hose on hose" (HOH) tecnique extracts a bit more heat from the coolant into the vegoil.
From the right tank outlet, coolant goes through a 2cm (3/4") ball valve that is easily reached from outside the vehicle without crawling under. This allows the heat to the fuel system to be cut off when the tanks are empty.
After the ball valve, coolant goes through the Webasto auxiliary coolant heater, then returns to the engine via another "T" in the cab heater coolant return hose.
Fuel
I used over nine meters (33') of rubber 1 cm (3/8") tubing for the fuel plumbing. When the whole thing was plumbed, I fired it up, leak-checked, then went back and covered all the added plumbing with foam pipe insulation.
Connections were via brass hose barb fittings and stainless steel hose clamps.
Aux Heat
This runs on biodiesel and solar panels, and is used to pre-heat engine coolant. This can be used to warm-start the engine, as additional "boost" engine heat while driving in frigid conditions, or as passenger camping heat while parked with the engine off.
Unfortunately, I haven't gotten the Webasto to work. I'm going to dig back into it in early 2005, and rip it out for warranty replacement, if necessary.
Issues/Problems
- The biggest problem to solve is getting the Webasto working! This item is a necessity for winter use, and I'm planning to drive to Canada in Februray 2005! --This has been a continuing source of frustration. I took it to the dealer for warranty repair, they said they fixed it, but Webasto wouldn't cover it under warranty, and billed me over $900! And it still doesn't work! Needless to say, I will not be paying that bill, and will do everything in my power to dissuade others from buying a Webasto product.
- In a few cases, I joined the 1 cm hose with smaller barbs, for example, the Pollak valves (used to switch between Fill/Recirculate, Left/Right vegoil tanks, and Biodiesel/Vegoil.) have three ports that are 1cm (3/8"), and three that are 0.8cm (5/16"). I suspect I'm leaking some air around these.
- I used inexpensive, fuel-grade rubber tubing, which may be damaged by vegoil over long periods, or by biodiesel over shorter periods. I'd like to be able to store biodiesel in the vegoil tanks -- or even be able to re-configure things as a mobile biodiesel processor someday. This will require re-plumbing with about $500 worth of expensive Viton tubing.
