newmercman:
Those smaller diesels don’t go out with a bang like a big long stroke one doesAlthough it didn’t really happen, we’ve been assured by an expert that it’s impossible
I was thinking more about all that hot water spraying around 
And we all know the definition of an expert, don’t we.
when I were lad, all motorbikes had an on/off fuel tap below the tank
and
before wagons had “key” start, you had to switch on the electrics and then start the engine. Switching off the “ignition” had no effect. You had to pull the stop button.
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newmercman:
Those smaller diesels don’t go out with a bang like a big long stroke one doesAlthough it didn’t really happen, we’ve been assured by an expert that it’s impossible
Bking, whats your expert verdict this time?
Ofcourse, its not really running off its own lube oil, that’ll be fairy dust!
Kelvin K series diesel marine engines had a very basic Woodward governor on them that you had to keep topped up with oil, fail to do that and they would run away with you and then run on their own lube oil until destruction, as one person called Barry W**** found out to his severe injury with bits flying around the boats engine room. Hand crank to start on petrol then once up to speed throw a lever to fire on diesel, max revs 750, each pot 22hp and you could get a 22, 44, 66 or 88 hp.
peterm:
What a berk on the bike. WTF was he going to do if he got to the air intake / venturi / airbox, stick his hand over it ? He was lucky he didn’t get both of them an ambulance ride. Does B.King ride a motor bike I wonder.
Take his jacket off and stuff it up the air intake?? The air intake was probably near the grill and probably not that big.
At least he bloke tried to help, noone else did.
And Bking gets proved wrong … Again !!
Oh dear, here’s an idea for the disbeliever, go and do an oil change on a mercedes sprinter non turbo (601 engine), but instead of putting 9 litres of oil back in, put 12 litres in instead. Then go take it for a little roadtest and report back your findings. Feel free to explain the uncontrollable reving and the clouds of white smoke. Obviously it cant be running on oil as you say thats not possible. Expert? in what exactly?
edited to add. An diesel engine will run on old engine oil, I know of a few people who run land rover td5’s on a 50% mix of diesel fuel and used filtered engine oil. The difference is, it is controlled by the fuel system (injectors/ecu on a modern common rail or pump governors/injectors on an older engine) A runaway engine is getting an unlimited, uncontrolled supply it can run on, hence the uncontrollable over revving, and clouds of smoke. The ultimate destruction is caused by the increased engine speed which most diesel engines were never designed to run at, and in the case of a turbo failure, the reduced oil pressure feeding the vital components.
The only ways to stop it are to cut off the supply of air (block air inlet) or to stall the engine using the highest possible gear.
Oh by the way the function of the gearbox is an engine speed and torque multiplier. Whilst you are correct in that engine speed and torque at the flywheel is unchanged, the load applied to it is.
Just read through some of this thread, and I can confirm that I’ve seen a few Ford Galaxy diesels that had revved to destruction after turbo failure from back when I was a Ford Technician.
A diesel will most definitely run on engine oil, it doesn’t need to be injected by the usual injector - that serves only to make sure that combustion occurs at the right time, and also efficiently (by atomization, and more lately by multiple injections per burn - TD5 Landrover for example). All oil is prone to oxidation when in contact with oxygen, the diesel engine exploits this by compressing (and therefore heating) the air so that when fuel is introduced it will burn, either efficiently and cleanly via injection, or inefficiently and dirty by larger drops of engine oil. Engine oils have anti-oxidants added to slow/prevent oxidation outside of the combustion chamber.
To further prove that oil oxidises with oxygen, note that on an oxygen bottle there is explicit instruction NOT to oil the threads of the regulator for this very reason.
Also, there was talk earlier in the thread of correct fuel to air ratio. In a diesel there is only the situation of too much fuel, never too little. The engine draws as much air as it can, or is forced in via turbo - with no restriction, unlike the ‘throttled’ petrol engine. The engine power or speed is governed only by the amount of fuel, not by the volume of air. This is why a diesel gives better fuel economy than a petrol, as compression is always high, even on closed throttle. Petrol engines when on part throttle run at reduced compression due to not being able to effectively replace the depression in the cylinder with enough air/fuel mix. Petrol has to be close to 14.7:1 to be ignited by spark.
Digressed a little there - but a diesel certainly will run on its own oil, the above attempts to explain why.
Bkings problem seems to be the total inability to understand that a turbocharged directly injected diesel engine will run on fuel that gets into the cylinder indirectly without being timed by way of the inlet manifold on the inlet stroke just as an indirectly fuelled petrol engine does.In the case of a diesel engine oil will burn under compression ignition.In addition to confusing the purpose of the turbo in being just a compressor which won’t act as a throttle valve if it stops working.The engine will just run on a naturally aspirated basis in that case.
I have seen a Petters engine run away in our workshop and it sheared the crankshaft at the flywheel and it took off across the workshop floor up the wall and thro a window into the yard lucky nobody was killed/hurt but was scary when you see it happening the force that built up in that flywheel!!!
I have been driving for decades, but must admit this thread was a complete eye opener for me. Apart from highly tuned race machinery self destructing, I had never even heard of the term runaway engines before and especially not relating to diesel engines.
As they say, you learn something new every day 
LIBERTY_GUY:
As they say, you learn something new every day
Some folk don’t though unfortunately.
perhaps this is an age related thing and modern engines don’t do it frequently, certainly as a newby many years ago, it was regarded as not very surprising if an engine did it.
You think a diesel runaway is scary then check this out. Apologies if posted before when thread drifted onto train stuff.
m.youtube.com/watch?v=E54HUQYeFNg
The loco was overfilled with water at its last stop.The crew were mainline staff and not experienced on the loco. The Engine started a slip on the damp rails which was badly controlled by the driver. The shock of the slip primed the boiler, sending water into the regulator, jamming it open. The driver attempted to then wind back the reverser, but the force of the motion spun it back, shattering the bones in both his arms. The loco was now driverless with just a fireman and pretty much blew itself to pieces.
Guess who’s motor just got blown at the MOT test station today?? 
Yep!! My mrs took her old MK3 diesel Mondeo for test today. During the smoke test rev-up, the ■■■■■■■ thing ran away!
A mate of mine owns the garage and he tried to stop it using top gear but it killed the clutch and I also think the engines stuffed because it apparently dumped a lot of water so its probably cooked it aswell! He well and truly crapped himself to by all accounts.
To be honest though the motor had 185’000 miles on it and I knew the turbo was dodgy on it anycase. I only paid 400 for the car so Il put this one down to experience!
Mind you, according to Bking I guess we’re all imagining it.
Gembo:
Guess who’s motor just got blown at the MOT test station today??Yep!! My mrs took her old MK3 diesel Mondeo for test today. During the smoke test rev-up, the [zb] thing ran away!
A mate of mine owns the garage and he tried to stop it using top gear but it killed the clutch and I also think the engines stuffed because it apparently dumped a lot of water so its probably cooked it aswell! He well and truly crapped himself to by all accounts.
To be honest though the motor had 185’000 miles on it and I knew the turbo was dodgy on it anycase. I only paid 400 for the car so Il put this one down to experience!
Mind you, according to Bking I guess we’re all imagining it.
Yes I took a friends Focus diesel for test a couple of years ago and the turbo decided to expire during the test! Very common on those apparently according to the firm that rebuilt the turbo. Anyway it revved its nuts off, couldn’t see the workshop for grey smoke, and kept on going with the key turned off. Luckily the fitter managed to block the inlet (never seen an airfilter hose removed so fast!) and it finally slowed to a stop. No real harm done, I refitted the rebuilt turbo for him and he then sold it on quickly, I still see it around though.
Pete.
yeah, I just pulled the turbo inlet pipe off it and the turbo is well and truly totalled!
Turbo shaft has more slop than a dutch ■■■■■■ and the sump is empty!
It’l be going for scrap.
Send it round to bum boy king, he’ll have it fixed in no time cos it couldn’t have done what you reckon.
peterm:
Send it round to bum boy king, he’ll have it fixed in no time cos it couldn’t have done what you reckon.