Make your own Biodiesel Part 1
There are at least 3 methods to run a diesel engine on biofuel utilizing vegetable oils, animal fats or both. All 3 are utilized with both fresh and secondhand 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 blend it with a solvent, or with fuel;
3. Convert it to biodiesel.
The very first 2 methods sound easiest, but, as so frequently in life, it's not quite that simple.
1. Mixing it
Grease is much more viscous (thicker) than either petro-diesel or biodiesel. The purpose of blending it or blending 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 mixing veg-oil with petroleum diesel or kerosene (like # 1 diesel) you're still utilizing fossilfuel-- cleaner than many, but still unclean enough, many would say. Still, for every single gallon of
grease you use, that's one gallon of fossil-fuel saved, and that much less climate-changing carbon in the atmosphere.
People utilize various blends, varying from 10% vegetable oil and 90% petro-diesel to 90% veggie oil and 10% petro-diesel. Some people simply use it that method, launch and go, without pre-heating it (which makes veg-oil much thinner), or even utilize 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 a very difficult and tolerant motor-- it will not like it however you probably will not kill it. Otherwise, it's not smart.
To do it properly you'll require 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 need for the blends.
Blends with numerous solvents and/or with unleaded gas are "experimental at best", little or absolutely nothing is learnt about their impacts on the of the fuel or their long-lasting results on the engine.
Higher viscosity is not the only issue with using grease as fuel. Veg-oil has different chemical homes and combustion characteristics from the petroleum diesel fuel for which diesel motor and their fuel systems are designed.
Diesel engines are modern makers with extremely precise fuel requirements, especially the more modern, cleaner-burning diesels (see The TDI-SVO controversy).
They're hard however they'll only take so much abuse. There's no guarantee of it, but utilizing a blend of up to 20% veg-oil of great quality is said to be safe enough for older diesels, especially in summertime.
Otherwise utilizing veg-oil fuel requires either an expert SVO option or biodiesel. Mixes and blends are typically a poor compromise. But mixes do have an advantage in cold weather condition.
Similar to biodiesel, some kerosene or winterised petro-diesel fuel combined with straight grease decreases the temperature at which it starts to gel. (See Using biodiesel in winter) More about fuel mixing and blends.