Fuels needed: WVO, RUG
Process:
1) 10 gallon drum with element heater, thermostat set to 74 degrees IIRC.
2) Run through dual filtering system to 1 micron.
3) Add RUG at 15% ratio, shake/blend well
4) Let settle. It will settle out into several layers. Top layer animal fat, middle is final product, bottom something wierd.
5) Pour solution through coffee filter, jeans, etc. The filters pull out the junk. You are left with the good fuel, which is very fluid with good viscosity!
6) Put into tank. I have a VW 1.6td IDI and I have just run 100% of it. Works perfect and has good viscosity. It was 16 degrees last night and still had good viscosity, marginally thicker then ULSD. Add diesel into the mixture to augment (if needed) but no more than 15% gas.


FYI: I have 1 tank the stock one, and NO fuel heaters. You don't need them and I think that should be proven. Nor is this forum about fuel heating

I have not had my oil to "settle out" like that. I always have a very very thin settling on the bottom which I assume is water from condensation inside the storage barrels. However my oil was much thicker at 18 degrees last week.

I hope you are carrying many spare vehicle fuel filters, I have to do a lot more work than that and still find you are pushing your luck once the weather drops below freezing.