Make your own Biodiesel Part 1

There are at least three ways to run a diesel engine on biofuel utilizing veggie oils, animal fats or both. All 3 are used with both fresh and secondhand oils.

1. Use the oil just 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 gas;

3. Convert it to biodiesel.

The first two methods sound easiest, but, as so typically in life, it’s not quite that basic.

1. Mixing it

Grease is a lot more viscous (thicker) than either petro-diesel or biodiesel. The purpose of mixing 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 (very same as # 1 diesel) you’re still utilizing fossilfuel– cleaner than many, however still unclean enough, numerous would say. Still, for every gallon of

grease you use, that’s one gallon of fossil-fuel saved, and that much less climate-changing carbon in the atmosphere.

People use numerous blends, varying from 10% vegetable oil and 90% petro-diesel to 90% grease and 10% petro-diesel. Some people just utilize it that way, launch and go, without pre-heating it (that makes veg-oil much thinner), or perhaps utilize 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 a very tough and it won’t like it but you probably won’t kill it. Otherwise, it’s not wise.

To do it effectively you’ll require what amounts to an SVO system with fuel pre-heating anyhow, ideally using pure petro-diesel or biodiesel for starts and stops. (See next.) In which case there’s no requirement for the blends.

Blends with numerous solvents and/or with unleaded fuel are “experimental at finest”, little or absolutely nothing is understood about their results on the combustion characteristics of the fuel or their long-term effects on the engine.

Higher viscosity is not the only issue with utilizing grease as fuel. Veg-oil has different chemical properties and combustion attributes from the petroleum diesel fuel for which diesel engines and their fuel systems are created.

Diesel motor are high-tech devices with extremely accurate fuel requirements, especially the more modern, cleaner-burning diesels (see The TDI-SVO debate).

They’re hard but they’ll just take so much abuse. There’s no assurance of it, however utilizing a mix of as much as 20% veg-oil of good quality is stated to be safe enough for older diesels, particularly in summer.

Otherwise using veg-oil fuel needs either an expert SVO option or biodiesel. Mixes and blends are generally a bad compromise. But blends do have an advantage in cold weather condition.

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