Hang on....if you turn it off...then fuel solenoid is shut.....so no diesel getting to engine...am I right so far?
So it must be running on crank oil, though I aint never heard of that with a 10j or 12j.
 
normally only 2 reasons for a diesel runaway,knackered turbo oil seals or a worn engine chucking oil back through the air filter,think the op is a tad confused
 
had a diesel sherpa runaway,it was not turbo with a perkins prima engine,just stalled it,brought it home,pulled the small hose on the airfilter,taped a coke bottle to it so made a catch can
 
12j's can have an issue of running on engine oil mist if the crankcase is pressurised. Usually caused by either compression lost past piston rings/valves or head gasket, sometimes over full engine oil/diesel leak into oil.

On a naturally aspirated engine only two things can cause a runaway. One is as you say, the other is rising oil level, usually caused by coolant leaking into the sump, as happened to my Ford tractor! :(

The crankcase breather is much more common cause on Land Rover engines. A while back I pulled the rubber pipe off the inlet manifold on a mates na. When I saw the oil mist pouring out of it, I suggested he leave it off.
Sadly he ignored my suggestion, resulting in a spectacular runaway that smoked out half of Hayle town centre! :D:D
 
:confused: wtf compression ignition, only possible reason would be erratic fuel pressure affecting base idle or governor

Running out of diesel used to be my specialist hobby and not once ever did the revs increase.
This was on TDI and TD5
The reason I ran out so often? fuel was free and i was damned if I was going to pay for any if I didnt have to:D

Not sure whats happened to the quote bit there, was meant for blue beasty?
 
for defenders it's usually failed turbo seals. oil gets blown past the turbo seal and into the intake

air in the fuel lines.. he is procrastinating a bit too much.. it's made him loopy.


Sorry to hijack the thread but I'm currently having a similar issue with my 12J 2.5 NA deisel.

Revs increase on its own, holds for a few (5-10)minutes and then back to normal for a while, then repeats. Eventually stalling sometimes after an hour, sometimes after 20 mins. Really difficult to start but eventually it does and then back to step 1. Only this time it won't restart so I've given up. (Now looking for a mobile mechanic between Notts and Derby.)

I thought perhaps air at first, so bled the system- no joy.

Does anyone think perhaps it may be the injector pump seals as quoted above?
 
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Sorry to hijack the thread but I'm currently having a similar issue with my 12J 2.5 NA deisel.

Revs increase on its own, holds for a few (5-10)minutes and then back to normal for a while, then repeats. Eventually stalling sometimes after an hour, sometimes after 20 mins. Really difficult to start but eventually it does and then back to step 1. Only this time it won't restart so I've given up. (Now looking for a mobile mechanic between Notts and Derby.)

I thought perhaps air at first, so bled the system- no joy.

Does anyone think perhaps it may be the injector pump seals as quoted above?

No! :)

Either your engine is knackered and beginning to run on oil, probably due to rubber pipe to inlet manifold ^^^^^^^^^^^^^.
Or a remote possibility your injector pump is giving up the ghost! ;)
 
No! :)

Either your engine is knackered and beginning to run on oil, probably due to rubber pipe to inlet manifold ^^^^^^^^^^^^^.
Or a remote possibility your injector pump is giving up the ghost! ;)


Ahh. I have noticed white mist if I take off the oil filler cap.

Any ideas how I can test either diagnosis? Assuming of course I can get the flipping thing started again. ( turning over only now )

Thanks
 
Ahh. I have noticed white mist if I take off the oil filler cap.

Any ideas how I can test either diagnosis? Assuming of course I can get the flipping thing started again. ( turning over only now )

Thanks

Take the rocker box cover off and start up, often a head gasket blow will be pretty obvious! :D

Starting probably isn't due to hg, that will be fuel or air fault or knackered injectors or ip! :)
 
There's no loss of water and no milky residue in filler cap. Also power isn't a problem( well at least last night when it was running, I got 50mph until the it died. Towed it home. Rebled the fuel and it ran fine. Doesn't sound like the head does it?

Think I'm looking at a new pump. [emoji22]££££'s
 
There's no loss of water and no milky residue in filler cap. Also power isn't a problem( well at least last night when it was running, I got 50mph until the it died. Towed it home. Rebled the fuel and it ran fine. Doesn't sound like the head does it?

Think I'm looking at a new pump. [emoji22]££££'s

You asked, I told you, you don't need to listen if you don't want to! :rolleyes:

If you have crankcase pressure it is very likely a blown head gasket, there will be no loss of water, or any water in oil, because it is just blowing from the cylinder into the pushrod tube, which pressurises the crankcase.

You may have a blown head gasket, if there is a lot of pressure with your hand over the filler cap on rocker box you probably do.

Sounds like there is also an issue with fuel system, either leaks or a shagged ip at a guess. :)
 

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