There are at least three methods to run a diesel engine on biofuel using vegetable oils, animal fats or both. All 3 are utilized with both fresh and pre-owned 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 easiest, however, as so frequently in life, it's not quite that easy.

1. Mixing it

Grease is a lot more thick (thicker) than either petro-diesel or biodiesel. The function of blending it or blending it with other fuels is to reduce the viscosity to make it thinner so that it flows 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 the majority of, but still not clean enough, lots of would say. Still, for each gallon of

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

People use numerous blends, ranging from 10% grease and 90% petro-diesel to 90% grease and 10% petro-diesel. Some people just utilize it that method, start up and go, without pre-heating it (which makes veg-oil much thinner), and even use pure veggie oil 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 will not like it but you most likely won't kill it. Otherwise, it's not wise.

To do it correctly you'll need what amounts 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 need for the mixes.

Blends with different solvents and/or with unleaded gas are "experimental at best", little or absolutely nothing is understood about their impacts on the combustion attributes of the fuel or their long-term results 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 developed.

Diesel engines are modern machines with extremely accurate fuel requirements, especially the more contemporary, cleaner-burning diesels (see The TDI-SVO controversy).

They're difficult however they'll only take a lot abuse. There's no warranty of it, however utilizing a mix of up to 20% veg-oil of great quality is stated to be safe enough for older diesels, particularly in summertime.

Otherwise using veg-oil fuel needs either an expert SVO solution or biodiesel. Mixes and blends are generally a poor compromise. But blends do have a benefit in winter.

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