Greased Lightning
Mark K February 4th, 2010
This is my “greasecar”, Stella. It’s a 1982 Mercedes 300 D (for diesel) that has been converted to run on used cooking oil. I took it to a shop in Oakland called Veg Rev where they did the conversion work. Diesel engines were originally built to run on a variety of oils – the only problem with cooking oil is that the viscosity is too thick. You can either have a conversion done to your engine so that the oil is warmed up and made thinner, or you can chemically convert the oil, producing biodiesel, and use this with a stock diesel engine.
Since we own two restaurants that produce about 15 gallons of used cooking oil each week, I decided to have the conversion done. The cooks at our restaurants know about my project, so they save the oil for me. Each Saturday, I go down to the restaurant and take about an hour to filter the oil through a simple sock filter and put it back into the five gallon containers. I also test the oil in a hot frying pan to make sure there is no water mixed in. Then when I need to fill up, I attach a funnel to my gas tank and pour the oil in. I haven’t bought diesel for about three months now.
We use canola oil at our restaurants. The oil comes from the rapeseed, and is grown in Canada. Not only is the fuel free, but it comes from a renewable natural resource. The carbon emissions that are produced by cars running on waste vegetable oil (WVO) are offset by the carbon dioxide being absorbed by the crop.
Filtering the oil, storing and pouring it into year tank can be a bit messy and time-consuming. You save money in the long run, but you have to do some work instead. A stop at the gas station might take five or ten minutes; filtering the oil and filling my tank might take over an hour. The thing that happens, though, is that you really begin to see the relationship between the fuel and the traveling – it feels good to know that you’re part of the loop and that you’re not just sending your money to an oil company or being indirectly involved in the politics of importing oil from the Middle East.
People always want to know if my car smells like french fries. Not exactly, I would say it’s more of a barbecued chicken aroma – it definitely smells better than diesel! The gas mileage and performance is about the same as when I use diesel – about 20-25 miles per gallon. If I’m on the road and run out of cooking oil, I can always fill up with diesel, or mix the two.
In the picture below, I’m filling up with Mazola corn oil. A friend of mine deep fried her turkey at Thanksgiving and then gave me her used oil afterward. So for a while, Stella was smelling like fried turkey!

I was already in a hurry when I pulled into the gas station. It was one of those discount stations that gets swarmed with customers when the price of gas is especially high. I maneuvered my way over near a row of pumps that was on the correct side for my gas tank and pulled up to the rear pump when the person in front of me finished.