As we have already established in the "Theory" section of this site, we need the following components to have a functioning vegetable oil fuel system which will not result in engine damage:

1) A tank to contain the vegetable oil. It should be constructed to the same specifications as the fuel tanks used in race cars. The tank should have an internal baffle to prevent the fuel from sloshing from side to side. It should be constructed from a material which will not react with the vegetable oil it contains. The area around the fuel pickup tube should be heated to insure that the fuel is thin enough to be drawn through the fuel lines without undue restriction.

2) Fuel lines to supply fuel to the engine and return unused fuel to the tank should be heated to thin the fuel enough to be drawn through the lines without undue restriction.

3) A fuel filter. This will also need to be heated so that the fuel can be filtered easily, in addition the filter itself should be an easily replaced part and readily available.

4) A final fuel heat exchanger capable of using engine coolant to heat fuel to the required temperature at maximum fuel flow.

5) Switching valves to switch between the two fuel systems. These should be independently controlled so that no cross contamination of fuel takes place and to speed the purging of fuel from the system.

6) A controller to switch the valves when the fuel is at the proper temperature and not before, to provide status indicators (Diesel mode, VO mode) to the driver, to provide an alarm if the vehicle is shut down while running on vegetable oil and to control the purging function so that the driver need minimal interaction and can devote his or her attention to driving as this is, after all, the point of the exercise.

I then set out to redesign a system from the ground up. I took each component separately and designed each to exceed its system requirements. We need the following components to have a functioning vegetable oil fuel system which will not result in engine damage:

1) The FRYBRID fuel cell is built from 5052 aircraft aluminum, all seams are hand TIG welded and the tank pressure tested. The internal baffle not only prevents fuel movement but isolates oil in the area of the fuel pickup and internal high efficiency in-tank heat exchanger which surrounds the fuel pickup and return lines, and all internal fittings are TIG welded to insure no possibility of leaks.

2) The FRYBRID heated fuel lines (patent pending) are made from fuel rated 3000 series aircraft aluminum fuel line, enclosed in a jacket of heated coolant, the fittings are rated for hydraulic fluids at high temperatures.

3) The FRYBRID heated fuel filter incorporates a high efficiency coolant to fuel heat exchanger through which the fuel passes and a standard Bosch diesel fuel filter with water drain.

4) The FRYBRID final fuel heat exchanger is extremely efficient and easily capable of producing 160F+ vegetable oil with 180F coolant under full engine load.

5) The FRYBRID system uses two solenoid valves which default to diesel, each is individually controlled.

6) The FRYBRID GEN-3 Microprocessor controls: Auto-switching to VO when proper temp has been reached insuring that cold oil does not enter the fuel system. Alarm warnings if shutdown without purging. Automated one touch purging cycle completely purges all VO from the fuel system before shutdown. Status indicators and override capability.




In this Diagram the basic layout of the FRYBRID system can be seen. The heart of the system is the FRYBRID GEN-3 Microprocessor which controls all system functions. It monitors coolant temperature witha special sensor and when it determines that the coolant temperature is sufficient for the final fuel heat exchanger to produce fuel at target injection temperature, it switches the system from Diesel to VO, turns off the "Deisel Mode" indicator and lights the "VO Mode" indicator.

A few seconds before the vehicle will be shut down the driver need only touch the "Purge" button on the dash and the FRYBRID GEN-3 will automatically initiate a purge cycle flushing all vegetable oil from the fuel system and displacing it with diesel fuel, turning off the "VO Mode" indicator and lighting the "Purge Mode" indicator, when finished the "Purge Mode" indicator goes out and the "Diesel Mode" indicator is again lit.

If the vehicle is shut down while running in "VO Mode" or during "Purge Mode" an alarm will sound and continue to sound until the engine is restarted and the FRYBRID GEN-3 will return the vehicle to "VO mode" unless the purge cycle is completed before shut down. This feature insures that the driver can not forget to purge the system before shutdown.

The system also features the capability to automatically initiate the purge cycle with an almost unlimited number of external sensors including: low fuel in the VO tank. In addition the unit may be commanded to switch to VO manually or completely disabled (Useful when lending your vehicle to those unfamilar with the system).

The controls inside the vehicle are simple and straightforward. A fuel level gauge for the vegetable oil tank, a push button to initiate the purge cycle, a toggel switch to override the system and three indicator lights (RED = Power on, vehicle in "Diesel Mode", GREEN = Vehicle on in "VO Mode" and YELLOW = "System Purging").


Our systems include: Automatic and Custom.

Each system has a heated VO tank, heated lines and a VO level gauge.

Automatic Operation:
The automatic system performs most of the change over automatically, it switched from diesel to Vegetable oil as soon as the coolant in the heat exchanger has reached operating temperature. Shortly before shutdown a "Purge" button may be pressed purging the system and returning it to Diesel operation, if the vehicle is shut down on VO a 10 second buzzer will sound and a light will flash above the "Purge" button reminding the operator to purge the system (this must be performed with the engine running). If the vehicle will be restarted in a short period, the operator may disregard the warning and exit the vehicle (an example would be stopping at a cafe to pick up a coffee or running into a store for a few minutes {dependent on climate}).

This system automates the "Purge" cycle via a custom made microprocessor which controls the cycle insuring that the VO is cleared from the lines, injection pump and injectors without accidentally filling the VO tank with Diesel, and resetting the system for Diesel operation. When the engine is restarted it again automatically switches to VO as soon as the temperature is within permissible range. This insures that the fuel system is purged and that the engine is always started on Diesel which eliminates the carbon buildup and subsequent engine damage associated with the use of unheated VO in unheated engines.

This is a custom panel and not included in the "Kit"

Typical scenario with the Automatic system:
The vehicle is started from cold, in a short time the system senses that the fuel/coolant heat exchanger has reached a permissible temperature and both the feed and return lines supplying the engine are switched from Diesel to VO, the "Diesel" indicator light goes out and the "Veg Oil" indicator is lit. The operator stops to pick up a coffee, switches the engine off and ignores the warning buzzer and flashing light above the purge button and exits the vehicle. Operator returns to the vehicle, starts and continues driving on VO, shortly before reaching his destination where the vehicle will be left for longer than 20 minutes, the operator presses the "Purge" button, the Microprocessor purges all VO from the fuel injection system and returns the system to Diesel operation, the "Veg Oil" indicator goes out and the "Purging" indicator is illuminated, when the purge cycle is complete the "Purging" indicator goes out and the "Diesel" indicator lights.

When the engine is shut down without Purging, the system automatically resets to Diesel operation unless the microprocessor determines that the exchanger temperature is within permissible limits. Were the vehicle to be shut down without purging and allowed to cool below 80F the vehicle would restart with some difficulty. Below 60F there would be considerable trouble starting and below 40F the engine would require preheating before starting and should be avoided.

Custom fabrication:
Custom systems can be fabricated for various applications and uses. We are a fully equipped workshop with Gas, Mig and Tig welding capabilities, knowledge of electronics as well as all automotive and truck systems.