VO in Coolant all of a sudden

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VO in Coolant all of a sudden

Postby Newtron » Thu Apr 18, 2013 12:55 am

After wiring the solonoids I tried everything out starting on diesel, and then I had diesel in the second tank for the sake of testing. This all went well pointing to the solenoids working just fine. Added WVO to the second tank to try a test run. Could not get my temp high enough so I never switched over.

What I realized was that my flat plate heat exchanger was routed wrong. I had the coolant and the fuel going the same direction instead of opposite directions. I re-routed it so that the coolant would actually flow to my heated fuel filter then back to my heated pick up then back to the engine. I assume since it was hitting a block at the FPHE it never made the additional loop thus not heating my filter or pick up.

So I switched everything and I ran the car to get up to temp and to get the coolant flowing thru the whole system. It still would not heat up. So I took the coolant hose off the pickup in the tank (to see if coolant made it back there)and VO/diesel mix came out. Then I opened the radiator and there is VO/Diesel mix in it too.

Could this be a result of not routing the FPHE correctly? Is there a leak in my line in line? Is my new heated pickup faulty? I also assume dont drive the truck (duh) and empty the coolant system. But how should I clean it? Then also could one do all the testing to see if the car will work on diesel, then on VO with just using water, and if so then drain the water and actually put in coolant?

Also when changing your coolant is the water pump stronge enough to displace air and move the coolant thru the system, or should you prime your coolant lines similarly to priming a pump? I ask this because after switching the FPHE to the correct flow the coolant lines to the filter and the heated pickup never really heated. There was just mainly fuel in the coolant hoses, they were not full or overflowing.

Thanks Everyone
1982 2x4 Diesel Pup Two Tank WVO System
1981 2x4 Diesel Pup DLX Long Bed
1986 4x4 Turbo Diesel Pup Space Cab (roomate moved out with it, but still see it often)

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Re: VO in Coolant all of a sudden

Postby Halden » Thu Apr 18, 2013 4:22 am

I would think the pump is strong enough to prime the system. I once ran with only about half the coolant needed and it cooled just fine. I once even ran it with with a really bad leak. A belt cut through my lower main hose and leaked a lot of my coolant out. It was over heating till I got it revved up a bit to build enough pressure pull the coolant up through the lower main. Cooled it down just enough to limp home. Though I was pulling about 3500 RPMs. I don't know about a system that extends to a WVO or anything to keep to warm, thats beyond my level of knowledge.
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Re: VO in Coolant all of a sudden

Postby jaredvd » Thu Apr 18, 2013 5:16 pm

if you have diesel and VO in the coolant it's probably from your FPHE being installed wrong. Could also be from your heated tank, if you have hose in hose, heated filter etc.
The way to test a WVO system is to get all the coolant lines routed tank empty.. warm the truck up and feel/take temperature readings at all parts.. check anywhere for leaks etc.
Then get close off your coolant loop (you should have ball valves to shut the flow to your WVO system off), put diesel in the WVO tank and flip it over to "WVO" as you would normally... flip it back.
Then open the coolant, test with diesel.. finally add in your WVO
As far as cleaning the WVO out of the radiator.. drain fill, run, drain fill run and so on till you feel like it's out.

Good luck
86 spacecab with 82 diesel swap