Hey everyone, I’m writing a book about a boy and no man-made electricity works around him (naturally occurring electricity works - lightening, static, cellular, etc.). A couple years ago you all helped me determine that an old truck with a Diesel engine could be started and continuously operate with out a electricity.
The car I chose was a 1946 Dodge Power Wagon with a Cummins Diesel engine. I want to confirm that if the character sticks a blow torch into where the glow plug was, the engine will start and run - is that true? Any short or longer term issues this will cause?
@texases - remember the thread about starting a diesel w/o electricity a while back? I’ve landed on a 1946 Dodge Power Wagon with a Cummins Diesel engine and starting it with a blow torch - would that work?
I’ve never seen a glowplug. But if it imparts heat to the combustion chamber, it’s one way to do that. Another way would be to screw in its place a bolt, for example, and heat the head of the bolt with a propane torch.
Everybody is a writer now-adays. At any rate this is how it works. You don’t necessarily need glow plugs to start a diesel depending on temperature. All glow plugs do is heat the chamber to make starting easier-like an initial spark plug. But to shut a diesel off, you need to stop the flow of fuel. This is accomplished with a shut off solenoid in the injector pump. You also need to activate the solenoid when starting the diesel to allow fuel to flow. Solenoids operate from battery power. Also you need some way to crank the engine over which will require greater rotation than a gas engine to start. So I suppose you could pull the solenoid or something to allow fuel flow and then rig up a hand crank or something but I think if I were in the bush, it might be easier just to develop a home made battery. At least that’s my half a million mile diesel experience. Give me a gas engine any day. A small gas engine doesn’t need anything except gas since it develops its own spark.
I’ve hand-cranked started a tractor with a diesel engine and no glow plugs and it’s no fun. It takes a bear of a man to get 2 revolutions on a diesel engine since the compression is so high. But there are many engines that were designed to be started that way. They were commonplace on farms in tractors.
Diesel is not particularly flammable or volatile and as such needs very high compression to ignite and get the combustion process started. Gasoline engines rely on spark plugs and have significantly lower compression. Since electric starters were a luxury for a long time here’s how it was done on a 40’s era McCormick-Deering WD9:
The engine was a standard diesel engine, hand crank to start. It’s about impossible to crank start a cold diesel, both because you’ll never turn the engine fast enough and because the diesel won’t ignite. So there was a lever that opened up compression relief valves in the head. Lowered the compression enough that a strong man could get a couple of revolutions if he had a good breakfast. But diesel won’t ignite, so the tractor has a one gallon gasoline tank. Switch another valve and you’re putting gasoline into the combustion chamber, which will light off and get the show going. A tractor engine with the compression relief open and running on gasoline makes a gawdawful racket like nothing else. But it’s running. Now the trick is to close the compression relief and switch to diesel fuel at the right rate and time to keep it running.