Re: oil vs cooking oil to run a loco?

In addition to the steam locomotives, cooking oil could be used to operate the diesels.

Corn oil, palm oil, canola oils etc. have a low enough auto-ignition
temperature that they should easily ignite from the engine compression cycle. Some oils such as peanut oil have a higher auto-ignite temperature and probably wouldn't work.

Four contradictions to using cooking oil are:

1. Cooking oil has a higher viscosity so in order to obtain effective transit in the upstream fuel system, the fuel would likely need to be pre-heated to about 150f. ( No big deal, boilers fired with #5 bunker used pre-heated fuel 100 years ago. I think that the UP Turbines also pre-heated their fuel)

2. Cooking oil has a different atomization signature, so the injectors would would likely need to be modified for best combustion efficiency.

3. The remains of yesterdays french fries, fried chicken and onion rings require a lot more filtering than distillate fuels. This would brign about increased filter and filter maintainance costs.

4. Finally, cooking oil that has served its purpose at the "greasy spoon" tends to have some oxidation characteristics that alters the Ph of the fuel. The increased acidity would tend to disolve the "innards" of the engine over time.

Nevertheless, used cooking oil could be used as an additive/extender to diesel, much in the same way as we now seem stuck with 10% ethanol in gasoline. A 50%/ 50% mix of cooking oil/diesel would probably be an acceptable diet for a prime mover.

So is it time to build a spur to the closest KFC?