WVO tank vacuum

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tim0574
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Joined: Wed Mar 01, 2006 6:50 am
Location: Wisconsin

WVO tank vacuum

Post by tim0574 »

I'm been running a 81 Rabbit for 6 months. It came with a decent wvo setup and I bought about 50 gallons of filtered veg oil from a guy a month ago. It's been a decent test but I have lots of little questions.

In the last few days I've noticed that I haven't been running proper temps, my thermostat is opening way too early. My coolant was already circulating into the coolant reservoir tank at 125 degrees.

What is the significance of the first long hash mark on the dash coolant gauge after the base line? How far does the needle typically run? I've measured it up to 180 with the needle 2/3-3/4 but down about 1/3 it still measures over 150.

The veg tank in back is a 5 gallon marine tank cut longwise, stainless steel coil inside with hose in hose running to it and welded back shut. One of the fittings also looks like it needed a custom weld. I've noticed vacuum release when removing the cap. At least I think that's what it is. Could it just be pressurized from the heat? If it's vacuum, it's not a good thing on the pump is it? The old ports on the talk for the fuel lines are likely blocked but I wondering if I should keep the cap loose until I install a vent on the tank to prevent the suction build up.

The line used for the veg looks narrower than the diesel line though I haven't measured it's size yet. Wouldn't that also be a constriction on the system especially if I haven't gotten the temps up correctly yet?

The system has the coolant hoses to the wvo tank teed in down by the water pump and up by the line under the heater control box with a 12v pump to circulate. I'm not sure what the best method for this is. The switch burned out on me so I haven't been used the extra pump lately and the heated coolant makes it the wvo tank fine. I'm concerned that if I do use the wvo pump, it may work against the stock pump since their flow rates would be different or I may burn out the wvo pump since it's always handling hot fluid. Is it mainly for use when the system is warming up? Will it harm the stock pump or make the belt slip? Is the stock pump able to handle the extra line circulation fine by itself?

I'll try to get some pics up soon.
Fatmobile
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Post by Fatmobile »

When you say pump you are always talking about the aux. coolant circulation pump right?

I've never used one.
The waterpump does fine on it's own.

You need to put a dash-mounted vacuum gauge on the fuel line.

A tank should always have a vent port,... I run the vent line to a 1 gallon jug.
If I backflush too long and overflow the tank it has somewhere to go,..
or I can fill the jug for long trips and it will be drawn into the heated tank, extending my range a little.
'91 Golf gasser converted to turbo diesel.
'83 Rabbit gasser, converted to diesel, then converted to run on vegetable oil.
2, '84 GTI projects cars
tim0574
Glow Plug
Posts: 19
Joined: Wed Mar 01, 2006 6:50 am
Location: Wisconsin

Post by tim0574 »

Ok, I'll fiddle with the unused fuel and air connections on the old marine tank, the guy probably sealed them up. He was good with the fabrications but was lacking in understanding of some of the other issues. The aux pump should be on a relay too. The switch burned out pretty quick when I used it and the wire diameter is too small anyway to match the line to the pump. I'm inclined to remove it altogether.

I think my veg filter is clogging as it was cycling in rpms even though my temps were good. Seems to take about 90 seconds at idle for the diesel to cycle in and smooth it back out.

I'm pretty much trying to refine the setup now. Too many clamps and hose size diameter changes.
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