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

1. Use the oil simply as it is-- normally 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 fuel;

3. Convert it to biodiesel.

The first 2 techniques sound easiest, but, as so frequently in life, it's not rather that basic.

1. Mixing it

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

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

grease you utilize, that's one gallon of fossil-fuel saved, which 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 people simply use it that method, launch and go, without pre-heating it (that makes veg-oil much thinner), or even utilize pure grease 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 tough and tolerant motor-- it will not like it but you probably won't kill it. Otherwise, it's not wise.

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

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

Higher viscosity is not the only issue with utilizing grease as fuel. Veg-oil has various chemical homes and combustion characteristics from the petroleum diesel fuel for which diesel motor and their fuel systems are designed.

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

They are difficult but they'll only take so much abuse. There's no warranty of it, but using a blend of approximately 20% veg-oil of great quality is stated to be safe enough for older diesels, especially in summer season.

Otherwise utilizing veg-oil fuel requires either a professional SVO service or biodiesel. Mixes and blends are normally a poor compromise. But mixes do have an advantage in cold weather condition.

Similar to biodiesel, some kerosene or winterised petro-diesel fuel combined with straight grease reduces the temperature at which it begins to gel. (See Using biodiesel in winter) More about fuel mixing and blends.