you could try watching "the colony" its a survival tv show but they show you how to render the fats (i think in season 2) from some decomposing pigs and use it to power a diesel tractor engine! quite interesting some of the stuff they do like forging a machete (season 2) and turning a petrol lawnmower into a generator by running it on wood gas (season 1)
-Pacman
-Pacman