Whenever we talk about biodiesel, we are referring to the process of converting used vegetable oil into an alternative fuel called biodiesel (or biodiesel conversion) which is then poured into tanks of unmodified diesel instead of petroleum-based diesel. There is, however, another practice that comes to mind for many whenever the term “biodiesel” appears. This phenomenon involves conversion of the engine rather than the oil, modifying a normal diesel engine so that it can run on unmodified residual vegetable oil (grease, grease, lard, etc.), essentially making it a “biodiesel engine” .

Hence the now famous and aptly named Grease Car. With the grease car being one shining example of many, the conversion of the engine to biodiesel is gaining wide appeal and it is no wonder – imagine pulling up behind McDonald’s and getting all the free fuel you can carry! It’s true. Restaurants have to pay for waste vegetable oil to be disposed of. People who need to power a biodiesel engine are doing them a favor: they get it for free.

Many fast food restaurants, in fact, prefer that you build committed relationships with them, coming in regularly to pick up a steady amount. That way, they can adjust their contract with their waste disposal provider accordingly.

A New York City man has driven over 3,000 miles in his modified 1985 Mercedes pickup with a biodiesel engine on free frying oil he gets from the corner deli.

Conversion of the engine to biodiesel appeals to many because it is a one-time process, while converting to biodiesel must be done every time the tank runs low. However, with the booming rise of biodiesel filling stations across the country, that advantage won’t weigh so heavily for long.

If you are interested in having a biodiesel engine of your own, you can purchase packaged biodiesel engine conversion kits to help you out. These conversion kits come with complete instructions and all the necessary equipment to modify any diesel-powered car to run on pure waste vegetable oil.

You can even buy a heavier-duty biodiesel engine conversion kit built especially for heavy-duty trucks.

Once a standard diesel engine is converted to a biodiesel engine, may it still runs on regular petroleum-based diesel (which is a very good thing – imagine being stranded at a gas station because there’s no vegetable oil in sight!)

Used vegetable oil in a converted biodiesel engine must first be filtered to avoid clogging fuel lines. In fact, it is recommended to filter it more than once, through increasingly smaller mesh filters (they are measured in “microns”, the finer the mesh the lower the number of microns). You can find filters of different sizes at most auto supply stores.

Now, there are many among us who, well aware of our own mechanical limitations, would not want to risk “tinkering” with our cars in such a way, and most of the biodiesel information on this website will be directed primarily at these people, with such information as where to buy biodiesel fuel and how to do your own biodiesel conversion. However, if you feel empowered to convert your diesel engine to a “biodiesel engine”, more power to you. Get yourself a kit or an entire book on the subject and then be on your way. And whichever route you choose, we wish you the happiest of journeys!