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

1. Use the oil simply as it is-- normally called SVO fuel (straight grease);

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

3. Convert it to biodiesel.

The first 2 techniques sound simplest, but, as so typically in life, it's not rather that simple.

1. Mixing it

Grease is a lot more viscous (thicker) than either petro-diesel or biodiesel. The purpose of mixing it or mixing 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 (exact same as # 1 diesel) you're still using fossilfuel-- cleaner than a lot of, but still not tidy enough, numerous would state. Still, for each gallon of

grease you use, that's one gallon of fossil-fuel saved, which much less climate-changing carbon in the environment.

People use numerous blends, varying from 10% grease and 90% petro-diesel to 90% grease and 10% petro-diesel. Some people just utilize it that way, launch and go, without pre-heating it (that makes veg-oil much thinner), or even use 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 difficult and tolerant motor-- it will not like it however you most likely will not kill it. Otherwise, it's not wise.

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

Blends with various solvents and/or with unleaded fuel are "experimental at finest", little or absolutely nothing is understood about their effects on the combustion characteristics of the fuel or their long-term effects on the engine.

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

Diesel motor are state-of-the-art machines with extremely exact fuel requirements, especially the more contemporary, cleaner-burning diesels (see The TDI-SVO debate).

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

Otherwise using veg-oil fuel needs either a professional SVO service or biodiesel. Mixes and blends are typically a poor compromise. But mixes do have an advantage in winter.

Just like biodiesel, some kerosene or winterised petro-diesel fuel combined with straight veggie oil reduces the temperature level at which it starts to gel. (See Using biodiesel in winter) More about fuel blending and blends.