Runaway Diesels?

[Whitespirit66]

What's gone wrong to make this happen? Why so much white smoke from the exhaust? Coolant? How would you stop the engine if it happened to you?

https://www.youtube.com/watch?v=pPEDtKvt4lI

 

[Mursal]

Excessive back pressure in the sump, due to engine wear (piston rings). Unfortunately the sump is vented into the inlet manifold (not to the outside of the engine like older models) so the engine runs on the fumes, uncontrollably and can over rev and self-destruct. Some newer engines are allowing diesel into the sump due to problems and this also causes the same issues.
White smoke will be the excessive oil in the mix.
A failed turbo will give the same smoke but engine revs will be within controlled limits.

 

[HERTS P&D]

You would have to stall the engine to turn it off.

Andy

 

[Dave54]

Too much oil in the sump. gets sucked up past the rings and engine runs on it being a diesel.

From what I've heard, once it does that, it runs until it runs out of oil or explodes. The answer is not to be too close to it. . .

 

[Whitespirit66]

Thanks for the replies. So, it's not actually running on the fuel from the tank.

As for stopping the engine, would best way to do this put foot on brake, handbrake full on, engage top gear and let clutch out? Hopefully saving the engine?

Or would you just get well away from it?

 

[HERTS P&D]

This is quite common in Transits, the answer is to stall the engine before it runs out of oil and needs a new engine.

Andy

 

[Burnerman]

Sadly, turbo failure can result in this self destruct situation......stall the motor or stuff a rag in the air inlet - if you have the piece of mind!
John

 

[CylonRaider]

When the engine is screaming you can't get it in gear.

Simplest way is to stuff a BIG rag in the air filter.

 

[Belle427]

The engine will have self destructed before you find the intake opening or get the clips off

 

[Burnerman]

Only seen this from a distance......cops had closed the road.
A Nissan X Trail was about to meet its maker - never heard a diesel scream like that!
John

 

[alan333]

Years ago my father had a Ford A Series 4.5 ton tipper with a straight six engine (an old P reg, so around 1976?). It regularly ran on engine oil first thing in the morning, even after a rebuild. The conclusion was that the oil couldn't drain quickly enough from the top of the cylinder head while it was cold/thick, and ran down the valves into the cylinders. The "cure" was to start it for a few mins, then switch off for a few more, then use as normal.

 

[Peter.N.]

This used to be quite a common problem on old diesels and its surprising how long they can tolerate running at over max revs. As previously stated, stalling them is the obvious way, you should be able to get into top gear even at high revs if the gearbox synchro is good, otherwise block of the air intake.

Peter

 

[freddiemercurystwin]

Sadly megane's seem to suffer this fate.

 

[aaamusements]

CO2 fire extinguisher sprayed straight in the intake is another way to stop them. If you have one to hand!

 

[Whitespirit66]

On the video I posted, I think one of the clips shows a bloke wander over to the screaming vehicle and casually tip some beer from his bottle into the intake. This stalls it immediately.

Beer: is there anything it can't do?