RE: canola oil
The biodiesel I have seen used in a diesel VW Rabbit smells like french fries. It is burning it though, I think it is because it is a 4 stroke. A two stroke spits it out before it burns. (hopefully) I have seen biodiesel (vegetable oil) used on youtube with a model diesel, but they mixed it with castor oil or synthetic too I think. I would guess it smelled like french fries. MMM french fries.