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

1. Use the oil just 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 fuel;

3. Convert it to biodiesel.

The very first 2 techniques sound simplest, however, as so frequently in life, it's not quite that simple.

1. Mixing it

Vegetable oil is much more viscous (thicker) than either petro-diesel or biodiesel. The purpose of blending it or blending it with other fuels is to lower the viscosity to make it thinner so that it flows more easily through the fuel system into the combustion chamber.

If you're blending veg-oil with petroleum diesel or kerosene (same as # 1 diesel) you're still utilizing fossilfuel-- cleaner than the majority of, however still not clean enough, lots of would state. Still, for every single gallon of

veggie oil you use, that's one gallon of fossil-fuel conserved, which much less climate-changing carbon in the atmosphere.

People utilize various blends, ranging from 10% veggie oil and 90% petro-diesel to 90% grease and 10% petro-diesel. Some people simply utilize it that method, launch and go, without pre-heating it (which makes veg-oil much thinner), and even use 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 tough and tolerant motor-- it won't like it but you most likely will not kill it. Otherwise, it's not smart.

To do it appropriately you'll require what totals up 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 need for the mixes.

Blends with numerous solvents and/or with unleaded gasoline are "experimental at finest", little or nothing is known about their effects on the combustion attributes of the fuel or their long-term results on the engine.

Higher viscosity is not the only problem with using veggie oil as fuel. Veg-oil has different chemical properties and combustion qualities from the petroleum diesel fuel for which diesel engines and their fuel systems are designed.

Diesel motor are modern makers with extremely accurate fuel requirements, particularly the more modern-day, cleaner-burning diesels (see The TDI-SVO debate).

They are difficult but they'll only take a lot abuse. There's no warranty of it, however using a mix of up to 20% veg-oil of excellent quality is said to be safe enough for older diesels, specifically in summertime.

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

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