There are at least 3 methods to run a diesel motor on biofuel utilizing vegetable oils, animal fats or both. All 3 are used with both fresh and used oils.

1. Use the oil just as it is-- typically called SVO fuel (straight vegetable oil);

2. Mix it with kerosene (paraffin) or petroleum diesel fuel, or with biodiesel, or mix it with a solvent, or with gasoline;

3. Convert it to biodiesel.

The first 2 methods sound easiest, however, as so frequently in life, it's not rather that simple.

1. Mixing it

Grease is far more thick (thicker) than either petro-diesel or biodiesel. The purpose of blending it or blending it with other fuels is to reduce the viscosity to make it thinner so that it streams more freely through the fuel system into the combustion chamber.

If you're blending veg-oil with petroleum diesel or kerosene (like # 1 diesel) you're still using fossilfuel-- cleaner than most, however still not tidy enough, many would state. Still, for every gallon of

vegetable oil you use, that's one gallon of fossil-fuel conserved, and that much less climate-changing carbon in the environment.

People utilize different mixes, varying from 10% vegetable oil and 90% petro-diesel to 90% grease and 10% petro-diesel. Some individuals just utilize it that way, launch and go, without pre-heating it (that makes veg-oil much thinner), or perhaps use pure veggie oil without pre-heating it, which would make it much thinner.

You might get away with it with an older Mercedes 5-cylinder IDI diesel, which is an extremely hard and tolerant motor-- it will not like it however you most likely will not eliminate it. Otherwise, it's not smart.

To do it effectively you'll need what totals up to an SVO system with fuel pre-heating anyhow, ideally using pure petro-diesel or biodiesel for starts and stops. (See next.) In which case there's no need for the blends.

Blends with different solvents and/or with unleaded gas are "speculative at finest", little or nothing is understood about their impacts on the combustion characteristics of the fuel or their long-lasting effects on the engine.

Higher viscosity is not the only issue with using grease as fuel. Veg-oil has various chemical residential or commercial properties and combustion qualities from the petroleum diesel fuel for which diesel motor and their fuel systems are designed.

Diesel motor are modern devices with very precise fuel requirements, specifically the more modern, cleaner-burning diesels (see The TDI-SVO controversy).

They are difficult but they'll just take so much abuse. There's no warranty of it, however utilizing a blend of as much as 20% veg-oil of great quality is said to be safe enough for older diesels, particularly in summertime.

Otherwise using veg-oil fuel needs either a professional SVO service or biodiesel. Mixes and blends are normally a bad compromise. But mixes do have a benefit in cold weather.

As with biodiesel, some kerosene or winterised petro-diesel fuel combined with straight vegetable oil lowers the temperature level at which it starts to gel. (See Using biodiesel in winter) More about fuel mixing and blends.