There are at least three methods to run a diesel engine on biofuel using veggie oils, animal fats or both. All 3 are utilized with both fresh and used oils.
1. Use the oil simply as it is-- typically 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 gasoline;
The first 2 methods sound easiest, but, as so often in life, it's not quite that easy.
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 flows more easily 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 utilizing fossilfuel-- cleaner than a lot of, but still not tidy enough, lots of would state. Still, for every single gallon of
grease you utilize, that's one gallon of fossil-fuel saved, and that much less climate-changing carbon in the environment.
People use numerous blends, varying from 10% veggie oil and 90% petro-diesel to 90% vegetable oil and 10% petro-diesel. Some individuals simply utilize it that method, begin up and go, without pre-heating it (which makes veg-oil much thinner), or perhaps utilize pure vegetable 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 a really tough and tolerant motor-- it won't like it however you most likely will not kill it. Otherwise, it's not smart.
To do it properly you'll require what amounts to an SVO system with fuel pre-heating anyway, preferably using 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 fuel are "speculative at best", little or nothing is understood about their effects on the combustion characteristics of the fuel or their long-lasting results on the engine.
Higher viscosity is not the only issue with utilizing vegetable oil as fuel. Veg-oil has various chemical properties and combustion qualities from the petroleum diesel fuel for which diesel motor and their fuel systems are designed.
Diesel motor are high-tech machines with very accurate fuel requirements, particularly the more contemporary, cleaner-burning diesels (see The TDI-SVO debate).
They're tough but they'll just take a lot abuse. There's no assurance of it, however using a blend of approximately 20% veg-oil of good quality is stated to be safe enough for older diesels, specifically in summer season.
Otherwise utilizing veg-oil fuel needs either an expert SVO service or biodiesel. Mixes and blends are typically a bad compromise. But mixes do have an advantage in winter.
Just like biodiesel, some kerosene or winterised petro-diesel fuel blended with straight grease lowers the temperature at which it begins to gel. (See Using biodiesel in winter season) More about fuel mixing and blends.
