Tag Archives: conversion

First Veggie Run

This was taken last Friday, the 24th – the first time we successfully ran it on veggie oil.


Work on the bus started out strong, with two of Joe’s students helping us out. Mark arrived shortly after we started, and we were in full swing. We got all of the pieces of the refinery in place, and pumped some veggie oil around. The first filter we were using was very plugged up, so once we removed the filtering element, the oil flowed free. That filter is 25 microns (tiny), and the first in the series of filters. The veggie flowed through the pump quickly, and pumped both to the day tank or to the nozzle (so we can fill up other containers with veggie oil). We found a small leak in a weld on the bulk tank, but that can be easily fixed on Monday. Joe is pleased that nothing that we have done has failed us yet.

So with everything hooked up, the two pumps working, the two electronic valves working, we decided to try switching it to veggie. So we run the veggie oil from the bulk tank, through the filter, and into the day tank, get everything ready, and flip the switch…and it stalls out. Ok, that’s fine – just air in the lines. Even though we bled the lines before trying to start it, it’s not surprising that there is some air left. Try again, and it stalls out once we switch to veggie. Disappointing.

Maybe it’s not warm enough. We let it idle on diesel for a while, letting the coolant warm up the veggie a little more. This time, Joe switches quickly from diesel to veggie and back to diesel. We can hear the difference in the engine’s sound, and it comes dangerously close to stalling out again. He repeats this for about five minutes, slowly increasing the amount of time he leaves it on veggie. He gets up to about five seconds, and we can still hear the difference once the veggie enters the engine.

Confidence is building, and while we can hear the difference, the engine is no longer threatening to stall. Ten seconds on veggie. Then twenty. Then we just leave it on veggie, and it’s still running smoothly. Joe slowly brings the engine down to an idle, and it’s still running! Success! Joe tells me to go take a whiff of the exhaust to see what it smells like. Now, it turns out that no matter what fuel you’re running, it’s a bad idea to shove your head right next to the exhaust of the bus, because while it might not be diesel, it’s still exhaust. At point blank range, I can smell no difference, but as soon as I walk away from it, I can smell the french fry exhaust on me. I can still smell it in my shirt as I type this.

We pull the bus out of the garage, to give the bus some fresh air. Everything works great. We get some weird looks from the kids at baseball practice as we laugh and celebrate. So good news, everyone – it works! Bring on the veggie oil.