Elsbett Theory and Components

As best I understand the Elsbett single-tank SVO conversion kit, its operation is based on the following concepts:

• SVO fuel must be heated prior to entering the injection system to reduce its viscosity and avoid damage to components that are designed for use with lower viscosity petroleum diesel fuel
• When starting and running a cold engine, an auxiliary electric heating element heats the fuel within the primary fuel filter, while other components "persuade" the car to keep its glow plugs operating longer than normal
• Once the engine is hot, engine coolant circulating through a heat exchanger warms the incoming SVO, the electric fuel filter heater is turned off, and glow plug operation is returned to normal
• An auxiliary fuel filter, used in conjunction with a cut-off valve, is added to some cars to allow quick recovery should the primary filter become clogged

A simplified schematic appears below.

The Elsbett single-tank SVO conversion for TDI appears to consist of the following components:

• Larger diameter fuel supply line from tank to engine to more easily accomodate the higher viscosity of vegetable oil
• Heat exchanger which uses engine coolant to heat the fuel after it has travelled from the tank to the engine compartment
• Extra fuel filter for use in the event of primary filter clogging, and valve to control its operation
• Electrically-powered prmary fuel filter heating element
• Coolant temperature sensor and associated relays and resistors to control the filter heating element and influence the car's control of glow plugs
• New glow plugs that are mechanically and electrically compatible with the more demanding heating requirements of SVO fuel
• Modifications to fuel injectors for deeper cylinder penetration and higher injection pressure threshold, presumably to modify the injector spray pattern

Additional points:

• Elsbett does not heat the fuel tank - Alexander recommends mixing petroleum diesel fuel with the SVO in sufficient quantities to prevent gelling or clouding in the tank - he recommends storing and observing marked glass bottles (e.g. 10/90, 20/80, 30/70, etc.) of various SVO/diesel mixtures outside during the winter to guide your choice of diesel fuel quantities.
• Alexander leaves the original fuel line in place, saying that many Elsbett customers in Europe use it to supply diesel fuel from an auxiliary tank in the spare tire area to an auxiliary coolant heater inside the driver's side front bumper/fender. Such devices are available for about 850 Euros and may include remote controls to start the heating process before going out to your car. He notes that in addition to the easier starting and lower stress on the engine, it provides better passenger comfort since the heater will work instantly. Todd had an electric block heater installed in his Golf, providing similar benefits, but requiring an electrical connection to all your cold weather parking spaces.
• Alexander strongly recommends the use of rapeseed (canola) oils. He points to higher heat value and lower iodine value statistics. He says that Elsbett's European customers predominantly use virgin (not waste) rapeseed oil. He also states, however, that the cost is approximately 0.75 Euro per liter. I am seeing much higher prices for Canola in Florida, although I haven't explored bulk sources. In addition, those of us approaching SVO from an environmental standpoint are keen to use waste vegetable oil and oil from alternative sources such as algae, so I'll be interested to hear about the ongoing experiences of workshop participants. Meanwhile, Eric Henry is now 18 months into using primarily soy-based WVO without problems. Hopefully the Elsbett system will prove itself over a wide range of oil sources as we pioneers put our diesels through the paces.

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