A diesel runaway is a phenomenon when worn piston rings start allowing oil from the engine block’s oil pan to syphon into the cylinders, where it combusts. Since it’s a diesel it does not have an throttle body so there’s plenty of air to create burning. This results in the engine running uncontrollably, eventually usually destroying itself if nothing was done to prevent it like stalling it.
Well on a diesel engine the throttle doesn’t control how much air is allowed into the cylinders but it controls how much fuel is injected. There’s always excess air in the cylinders, which is also the reason they’re so damn poluting.
Diesel engines work with high pressure to let the fuel spontaneously combust. Diesel is a fuel oil. This means the pressure in a compression ignition engine (diesel engine) is high enough to let fuel oil combust.
Engine oil breaks down as its used, it gets thinner. New engine oil won’t burn, but used engine oil will. The pressure needed in a compression ignition engine to let diesel combust is high enough to let used engine oil combust. So when used engine oil gets into the cylinders it acts like a fuel and it will burn.
Like Igor said, worn piston rings can let oil into the cylinders. But also a blown head gasket or worn valve guides can cause an engine to run away. A more real cause for a runaway is having too much oil in your engine. When you have to much oil in your engine you risk that the oil gets sucked up trough the cranckcase ventilation into the intake of the engine.
A diesel engine already has an unlimited supply of air, the only thing that limits the engine is the fuel supply. If in some way oil gets into the cylinders the engine also has an unlimited supply of fuel and it will run away. It will just start revving up until it explodes.
The only way to stop this is to either limit the supply of air so the engine drowns itself, or to stall the engine. If a runaway happens while you’re driving immediately pull on the hard shoulder. Come to a dead stop, pull the handbrake, put the car in the highest gear it has (5th or 6th or whatever) and take your foot of the clutch.
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A diesel runaway is a phenomenon when worn piston rings start allowing oil from the engine block’s oil pan to syphon into the cylinders, where it combusts. Since it’s a diesel it does not have an throttle body so there’s plenty of air to create burning. This results in the engine running uncontrollably, eventually usually destroying itself if nothing was done to prevent it like stalling it.
Well on a diesel engine the throttle doesn’t control how much air is allowed into the cylinders but it controls how much fuel is injected. There’s always excess air in the cylinders, which is also the reason they’re so damn poluting.
Diesel engines work with high pressure to let the fuel spontaneously combust. Diesel is a fuel oil. This means the pressure in a compression ignition engine (diesel engine) is high enough to let fuel oil combust.
Engine oil breaks down as its used, it gets thinner. New engine oil won’t burn, but used engine oil will. The pressure needed in a compression ignition engine to let diesel combust is high enough to let used engine oil combust. So when used engine oil gets into the cylinders it acts like a fuel and it will burn.
Like Igor said, worn piston rings can let oil into the cylinders. But also a blown head gasket or worn valve guides can cause an engine to run away. A more real cause for a runaway is having too much oil in your engine. When you have to much oil in your engine you risk that the oil gets sucked up trough the cranckcase ventilation into the intake of the engine.
A diesel engine already has an unlimited supply of air, the only thing that limits the engine is the fuel supply. If in some way oil gets into the cylinders the engine also has an unlimited supply of fuel and it will run away. It will just start revving up until it explodes.
The only way to stop this is to either limit the supply of air so the engine drowns itself, or to stall the engine. If a runaway happens while you’re driving immediately pull on the hard shoulder. Come to a dead stop, pull the handbrake, put the car in the highest gear it has (5th or 6th or whatever) and take your foot of the clutch.