Green Machine

“...what the restaurant kitchens dump, I want to pump, to fill the tank of my well-oiled machine...”

– Nat Keefe, "Well-Oiled Machine"

Our Well-Oiled Machine

As a touring band, we run into a dilemma: we must travel constantly, yet we wish to free ourselves from dependency on foreign oil, and all of the associated environmental, economic, and political problems. By fueling our tour bus with biofuel, we are able to travel extensively, yet tread lightly using a domestically produced, renewable fuel with reduced toxic emissions and a decreased carbon-footprint.

Our faithful tour bus, Seana (1983 MC-9) has been retrofitted with a special two-tank fuel system to run on biodiesel and recycled vegetable oil. There is no modification to the standard Detroit Diesel 8V-71 engine. In the past, we used the system to run on waste vegetable oil (WVO) from restaurant dumpsters. Presently, we use the same system to run on biodiesel, purchased from fueling stations around the country.

Extensive information about biofuels and our tour bus can be found in our Biofuels Learning and Resource Center.

click thumbnail to

see detailed two-tank

fuel flow diagram

click thumbnail to

see annotated picture

of SVO system

Running on Vegetable Oil

1. Collect the Oil. Any restaurant that prepares fried food has a dumpster out back for disposal of used vegetable oil. This oil is generally picked up by an oil collection service. The oil ends up either being used in animal feed, soap production, and biodiesel production, or being dumped in the land fill. This waste oil can be recycled and reused as fuel for a diesel engine. Using a Fill Rite12 volt DC fuel transfer pump, we pump the oil from the restaurant dumpster into our 120 gallon gathering/dirty tank. On the gathering end of our pump hose, we have a 150 micron strainer to filter out the larger food and debris.

2. Heat the Oil. Hot vegetable oil is considerably easier to filter, so both the gathering/dirty tank and the fuel/clean tank are fitted with aluminum coil tank heaters submerged in the oil. These coils are connected to the engine coolant lines; as hot coolant flows through the coils it heats up the vegetable oil to near 180 degrees Fahrenheit.

3. Filter the Oil. The hot waste vegetable oil will naturally separate into hot oil floating on top of water and debris. A hose attached to the bottom of the tanks allows us to drain off the water and debris. The hot oil can the

n be pumped through a filtration system to remove particles down to10 microns, and to filter out any remaining water. (Remember, the injectors in a diesel engine are approximately the diameter of a human hair, so any little leftover food debris can cause major injector problems. We use a Reverso 3 gpm gear pump to pull the oil from the dirty tank, through a Vormax 10 micron filter, and into the clean fuel tank.

4. Switch to Veggie! Once the oil is hot and filtered, we flip a switch at the driver's seat which activates four solenoids (electric valves). The diesel engine has two fuel lines — a send line delivering fuel from the tank to the engine, and a return line returning unburned fuel back to the tank. Flipping the switch activates the solenoids and opens up the send and return lines to and from the vegetable oil tank, and closes the lines to and from the diesel tank. We yell out triumphantly, "Switching over!"and then proudly continue down the road powered by biodegradable, domestically produced, used grease, the alluring aroma of the local burger joint wafting behind us.