Hey guys I have a 2006 L3400. The other day I was just driving a field and it ran away. Black smoke and high rev. I waited a bit and started it back up. Everything seemed fine, I drove it back home and parked it. Everything looks fine, but I am a little nervous, I don’t want to ruin the motor. Any suggestions or things to check? Thanks!
Help runaway diesel.
- Thread starter Egoldizen
- Start date
I don’t know your machine but of course excess fuel or oil was being fed to the engine. I just wanted to mention that it would be a good idea to have something ready to block the air intake completely before starting again to stop a run away.
85Hokie
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Check you engine oil level and or your hydraulic oil levels......... any of them low?
When I worked as a logger I was running a skidder and it ran away on me. It was an injector that opened up.
A diesel engine can runaway when ANY source of fuel gets into the intake plenum (engine-oil, hydraulic -fluid...etc) Engine oil can get into the intake thru bad seal within turbocharger. There are not many ways for hydraulic to get into intake. Another reason for runaway can be governor-failure.
As other folks have suggested, it is a good idea to have a PLAN to kill the engine if runaway happens.
For example: If engine oil is getting past turbocharger-seal.... the engine will NOT be able to be shutdown using normal means. (like the off switch)
THE ONLY WAY TO KILL ENGINE IS TO BLOCK AIRFLOW INTO THE INTAKE PLENUM. a block of wood to cover the air-intake is often used.
North Idaho Wolfman
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Start it and immediately and quickly feel the exhaust manifold right where it leaves the head, do any of the ports stay cold while it's warming up?
Have you checked your fuel cut-off solenoid? Sometimes it's the obvious things.
If you have a CO2 or a halon fire extinguisher, keep it with the tractor. You can put either one into the intake of a runaway engine with no harm to the engine. It will stop the runaway.
Do NOT use a dry chemical extinguisher! You will ruin the engine.
If you have a CO2 or a halon fire extinguisher, keep it with the tractor. You can put either one into the intake of a runaway engine with no harm to the engine. It will stop the runaway.
Do NOT use a dry chemical extinguisher! You will ruin the engine.
North Idaho Wolfman
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A faulty or failed fuel cut off solenoid can not cause it to Rev up and smoke.
If you can turn it off with the key that is not a "Run Away" , had that happen with my old JD, fixed it with a rebuilt fuel injector pump. I don't know if yours has a turbo, a bad turbo can give LOTS of black smoke when its burning oil.
North Idaho Wolfman
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This is very much a fluke, Kubota engines very very very rarely ever have any issue even close to this.
The last one that I worked on that the owner swore up and down ran away, only revved to the limit because of a broken return spring, no where near a run away.
I would say the most likely cause is either fuel contamination, seen several with gasoline in the "100% Pure Diesel" or a bad / failing injector!
The last one that I worked on that the owner swore up and down ran away, only revved to the limit because of a broken return spring, no where near a run away.
I would say the most likely cause is either fuel contamination, seen several with gasoline in the "100% Pure Diesel" or a bad / failing injector!
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Russell King
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Is the engine oil higher than it should be, could the hydraulic fluid be getting into the engine and then causing it to get into the cylinders somehow?
You mentioned that the hydraulic fluid was low so I am curious how low and where that fluid is now…
You mentioned that the hydraulic fluid was low so I am curious how low and where that fluid is now…
Ah, true. It can prevent shut off, but not cause a runaway.
But this guy can!
Well, I had a friend of mine who is a diesel mechanic come by. I Had just had the oil changed and they had it way overfilled. He said that when it thinned down that it can blow by and run away. No diesel smell in oil. Changed oil and filter, and ran it tonight for 45 min. No problem. I will have a block of wood under the hood incase this ever happens again. Thanks for all the advice! You guys are great.
How low was the hydraulic fluid? Did they happen to drain the transmission instead of the engine when they serviced it? Not sure if it’s a gear or hst trans, but if it’s a gear drive I would definitely make sure the hydraulic level is correct before driving it.
North Idaho Wolfman
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Keep an eye on both the engine oil level and the hydraulic oil level, as a bad seal on a hydraulic pump will move oil from the hydraulic system to the engines oil system.