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

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

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

1. Mixing it

Grease is a lot more thick (thicker) than either petro-diesel or biodiesel. The purpose of mixing it or blending it with other fuels is to decrease the to make it thinner so that it flows more easily through the fuel system into the combustion chamber.

If you're mixing veg-oil with petroleum diesel or kerosene (same as # 1 diesel) you're still using fossilfuel-- cleaner than most, but still unclean enough, many would state. Still, for every single gallon of

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

People use numerous mixes, varying from 10% vegetable oil and 90% petro-diesel to 90% veggie oil and 10% petro-diesel. Some people just utilize it that way, begin up and go, without pre-heating it (that 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 hard and tolerant motor-- it will not like it but you probably will not eliminate it. Otherwise, it's not smart.

To do it appropriately you'll need what totals up to an SVO system with fuel pre-heating anyhow, 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 gas are "speculative at finest", little or absolutely nothing is learnt about their results on the combustion qualities of the fuel or their long-lasting results on the engine.

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

Diesel engines are state-of-the-art devices with extremely exact fuel requirements, specifically the more contemporary, cleaner-burning diesels (see The TDI-SVO controversy).

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

Otherwise using veg-oil fuel requires either a professional SVO option or biodiesel. Mixes and blends are typically a poor compromise. But blends do have an advantage in cold weather.

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