Biodiesel or biofuels are diesels fuels that are made by reacting waste vegetable oil (WVO) with other common chemicals. Biodiesel or biofuels may be used in any diesel automotive engine in its pure form or blended with petroleum based diesel.
Due to unstable oil price situation in the world market, many countries have been looking for alternative energy to substitute petroleum. Researches on the use of vegetable oils as fuel substitutes in diesel engines have been done in many countries with success.
So can I run my diesel engine on biofuels, the answer is yes, but with that said some vehicles are more readily converted than others?
What makes your one vehicle better for Biofuel than another?
Fuel Pump: The higher viscosity of WVO (waste vegetable oil) is hard on fuel pumps.Stock mechanical fuel pumps are usually tougher than stock electric fuel pumps.Stock electric fuel pumps will most likely fail prematurely from WVO use.
Direct/Indirect Injection: It is widely considered that indirect injection engines are more acceptable to WVO use. The thinking behind this is that with indirect injection, fuel is injected into a pre-combustion chamber and unspent WVO (waste vegetable oil) would not be directly contaminating (coking) the piston and cylinder walls. Contamination of cylinder walls and piston rings would lead to blow-by and lubrication oil contamination. This will most certainly lead to premature engine failure.
Use: Vehicles/engines used for long continuous duration are more suitable for WVO (waste vegetable oil) than one used occasionally for short duration. Engines should not be started on WVO (waste vegetable oil) and hence, the required purge/shutdown procedure makes short duration use impractical.
It cost less expensive vehicles are inherently more acceptable to modify and have a good risk reward quotient. Older vehicles typically have less complex and more overdesigned components.
What do in need to convert my vehicle to run on WVO (waste vegetable oil)?
A single tank is an option but while this in the lowest cost conversion it is also the most risky and should be avoided If possible.
A single tank with a heated filter, injector line heaters and fuel coolant heat exchanger is very popular. But the Weakness in this system is in the initial startup cold un burnt WVO will be in contact with cold combustion chamber and cylinder walls. Ultimately, piston ring contamination and coking will occur and leading to lubrication oil contamination and pre-mature engine failure.
Next is a two tank system that can be manually switched from diesel to biodiesel when your engine is at running temperature what this does is produces higher combustion temperatures and more completely consume the WVO (waste vegetable oil) reducing contamination to the engine? The problem with this system is the drive needs to switch from diesel to biodiesel after the engine gets to operating temperature and switch from biodiesel to diesel and the residual WVO must be consumed leaving only diesel in the engine for the next cold starting. The weakness of this system is making the proper switching waiting until the engine is properly heated and back to diesel without allowing sufficient time for the complete purge of WVO from the engine.
The simplest to use is the two tank system with automated control it is the same as above but electronic sensors and timers control the switching of the diesel to biodiesel and vice versa.
This system provides the highest reliability and is a completely independent WVO system from the stock diesel fuel system.