There are at least three ways to run a diesel motor on biofuel using veggie oils, animal fats or both. All three are utilized with both fresh and secondhand 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 mix it with a solvent, or with gas;

3. Convert it to biodiesel.

The very first two approaches sound easiest, but, as so typically in life, it's not rather that simple.

1. Mixing it

Vegetable oil is far more thick (thicker) than either petro-diesel or biodiesel. The function of blending it or mixing it with other fuels is to reduce the viscosity to make it thinner so that it streams more easily 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 the majority of, however still unclean enough, many would state. Still, for each gallon of

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

People use different blends, ranging from 10% veggie oil and 90% petro-diesel to 90% grease and 10% petro-diesel. Some individuals just utilize it that method, begin up and go, without pre-heating it (that makes veg-oil much thinner), or perhaps utilize pure grease without pre-heating it, which would make it much thinner.

You may get away with it with an older Mercedes 5-cylinder IDI diesel, which is an extremely difficult and tolerant motor-- it won't like it but you most likely won't eliminate it. Otherwise, it's not smart.

To do it properly you'll need what totals up to an SVO system with fuel pre-heating anyway, ideally using pure petro-diesel or biodiesel for starts and stops. (See next.) In which case there's no requirement 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 qualities of the fuel or their long-lasting effects on the engine.

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

Diesel engines are modern makers with very accurate fuel requirements, specifically the more modern-day, cleaner-burning diesels (see The TDI-SVO controversy).

They are difficult however they'll only take a lot abuse. There's no assurance of it, however utilizing a mix of as much as 20% veg-oil of good quality is said to be safe enough for older diesels, especially in summer season.

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

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