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Matt, Mechanical Engineer
Category: UK Car
Satisfied Customers: 21720
Experience:  BEng hons Mech engineering, in auto industry 22 years
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how can you stop a runaway diesel engine

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how can you stop a runaway diesel engine

I'm presuming you're concerned about the situation where the turbo oil seal fails for example and the engine races off.

There are 2 options, you either stick in top gear and suddenly drop the clutch with the foot on the brake to try and stall the engine, this can damage the clutch as you'd imagine.

Or you choke the intake off with a load of rags to starve the engine of air, this is slightly dangerous as you have to get close to the engine revving its head off and the intake is not always easily accessible
Customer: replied 7 years ago.

I am still a little lacking in knowledge, what fuels the engine or is it the turbo, and where does it get the fuel from is the igniton is turned off. and can the source be turned off.


regards john


Diesels aren't throttled like petrol engines so the power is controlled by how much fuel is present in the incoming air, this fuel is normally provided by the injectors and carefully metered out, however if the turbo oil seal gives out then this will pump engine oil into the incoming air.

A diesel will happily run off this engine oil, and as the engine oil pump is driven by the engine crankshaft, its all mechanical and theres nothing to stop the flow of oil until the engine is stopped or the engine drinks all its own lubrication oil.
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