Rolled my 3240, and it ran till it blew ??

[westcliffe01]

Has anyone tried the CO2 proposal? At a high enough temperature even Nitrogen will oxidize in the presence of oxygen (thats where NOx comes from) so I would imagine that a screaming diesel running (rich) on its own oil would have no problem using CO2 as an oxidizer. CO2 works fine on combustion at lower temperatures. Remember that NOx is used as a performance booster for high performance engines.

I could see where plumbing an N2 cylinder directly into the manifold would work reliably, since there is no oxygen to dissociate. Probably a hassle obtaining one small enough though.

 

[PoorMansCat]

Has anyone tried the CO2 proposal? At a high enough temperature even Nitrogen will oxidize in the presence of oxygen (thats where NOx comes from) so I would imagine that a screaming diesel running (rich) on its own oil would have no problem using CO2 as an oxidizer. CO2 works fine on combustion at lower temperatures. Remember that NOx is used as a performance booster for high performance engines.

I could see where plumbing an N2 cylinder directly into the manifold would work reliably, since there is no oxygen to dissociate. Probably a hassle obtaining one small enough though.

wait.. Do you mean NOS.. not NOX.. NOX is a byproduct of combustion.. and pretty much useless

 

[Don87]

I appreciate all the varied opinions offered in this thread. My opinion is a little different. In my experience I have never seen or had a 4 stroke diesel engine run away, now I am not saying that they can't run away, just saying it is extremely unusual and extremely rare for it to happen. I have seen 2 strokes run till they grenade and for different reasons. 1- mechanical governor failure, (the most common but can create the drafting issue). 2- the scavenging of oil vapors from an engine with overheated oil.

Now with that being said I would like to offer a different scenario. If a diesel engine has glow plugs it is a lower compression engine that needs the glow plugs to heat the cylinder air to aid, or in some cases completely enable cold start combustion. Now here is my point, how does this lower combustion engine have enough compression to ignite straight engine oil let alone synthetic oil?

I think that oil was mixing with fuel, the fuel was running the engine and the oil was creating all the smoke. What are the chances of lets say, maybe a fuel rack sticking because it was on its side?

Another clue, of all the posts in this thread I did not see one time where it was stated that the engine ran to over speed, just that it was running at wot. I also think that the increasing volume of engine oil entering the combustion chambers is what actually shut down the engine.

I say check your ignition switch and safety switch's.

JMO folks, flame away.

Dunno where you came up with any of the things you posted, but WOW.

And as far as the 'bold' print that I highlighted..............I think you may have missed post number 2 on this thread. And you apparently know little about diesel engines.

A diesel engine requires 3 things.........

1) fuel.(diesel, motor oil, hydraulic oil, vegetable oil, etc)

2) compression.

3) air

'Switches' work on gasoline powered vehicles where they need 'spark' to operate

EDIT: And since you said "flame away"...........I'm going after the school that taught you apparent nonsense..............If I were you I would sue the h*ll out of them, for not teaching you proper mechanics!!!

 

[RobertBrown]

As I said I appreciate the ideas and if you want to rig up some kind of "rigged" CO2, fire extinguisher, exhaust gas re-router then that's fine but there is a already a "proven" system available.

Don't forget the potatoe!

 

[PoorMansCat]

Don't forget the potatoe!

No doubt... it will work, but if the engine is screaming wide open, GOOD LUCK with trying to stuff a potato up its tail end...

 

[DavidVT]

I had skipped over this thread several times but finally decided to read it. I am glad I did. Steve, I am glad you were not hurt. (Back in August when this thread started)

If for nothing else, everyone with a diesel engine should spend a few brain cycles considering how to shut it down if turning the key 'off' fails to stop it. Call it the 'plan b'. If it ever happens you are likely to recall this 'plan b' rather than finding yourself in a total panic.

I suggest there may be a peace of mind gained from learning a bit about shutting down your run away diesel in the perhaps unlikely, but technically possible, event it happens to you. Furthermore understanding a little about why it can happen is also worthwhile if you are the analytical type.

Years ago in the service I was taught the risk of a marine diesel injesting gasoline fumes via the air intake as one way for a run away to occur and for runaways we were taught to plug the intake (suffocate) to stop the engine. I read here in this thread about engine oil fueling the engine as another. I do not pretend to be a diesel expert but have come to understand this is a possibility due to the nature of diesels. The only thing close to a run away that I have ever witnessed was a sticking fuel shut off valve on a fork truck that failed to close. The look on the novice operators face when the keys were in his hand with the engine still running was priceless. (No high rev run away, just the failure to control as expected.)

Happy New Year...

 

[Hvytrkmech]

Wow man! Sorry I can't offer any ideas. Sure am glad your not hurt! At least your able to walk away.

Let us know tomorrow how it goes.

Did you mean this post? It was the second one I read. :confused2:

Dunno where you came up with any of the things you posted, but WOW.

And as far as the 'bold' print that I highlighted..............I think you may have missed post number 2 on this thread. And you apparently know little about diesel engines.

A diesel engine requires 3 things.........

1) fuel.(diesel, motor oil, hydraulic oil, vegetable oil, etc)

2) compression.

3) air

'Switches' work on gasoline powered vehicles where they need 'spark' to operate

EDIT: And since you said "flame away"...........I'm going after the school that taught you apparent nonsense..............If I were you I would sue the h*ll out of them, for not teaching you proper mechanics!!!

Thanks for the clarification and your opinion, are you sure I am the one not in the know?

How many class 8 truck engines have you worked on in the last 27 years of your life? If you have, then how many of those engines were involved in a roll over accident that resulted in a run away engine? I have worked on dozens of rolled engines and not a single one ever ran away. They were either shut down by the driver once on its side, seized by lack of lubrication, or the ecm shut it down. Even the older Cat and Cummins mechanical engines turned off with the simple turn of a key or pull of the shut down cable. While I knowingly admit to not knowing everything, especially like how diesel engines that run away usually seem to be industrial engines that spends their life working while standing. I will say that I try to relate real world experience and training for informational purposes only. I stand corrected for comparing class 6-8 truck experience to anything related to a Kubota tractor. Obviously its a huge mistake on my part, surely, never to happen here again.

Since you are so smart and apparently with all the answers, would the engine run away if an injector tip cracked or blew off and caused an over fueling of a cylinder? What happens when you need to operate your tractor, you get on it and turn the ignition key? Then you finish your task with it, then turn the ignition key off? Hmm, interesting what that electrical switch does, even more interesting on how many other electrical devices that one little switch controls. I know on my little B7610 that the ignition key can be inserted partially and turned, it can also be removed partially with the engine running then moved 360*.

You should fill your fuel tank with engine, hydraulic, veggy oil and let us know how that works out for you. Of coarse you could spend the coin to augment your equipment to burn some of these fluids, but have you or anyone else here on this board done so?

You should go after the schools that I have attended, I would love to hear what they say about your educational seminar. :laughing:

 

[Elkins45]

Hmm, interesting what that electrical switch does, even more interesting on how many other electrical devices that one little switch controls. I know on my little B7610 that the ignition key can be inserted partially and turned, it can also be removed partially with the engine running then moved 360*.

I'm a complete newbie with diesels, but when I turn the key to 'off' on my Kubota L2350 it doesn't do a darned thing. I have to reach down and pull up the fuel shutoff lever all the way to the top.

What could an electrical switch activate (or deactivate) to kill a diesel engine? A fuel shutoff? An air shutoff? Electrically activated compression release? What else? My little tractor doesn't have any of those things. There is absolutely nothing attached to my engine that uses electrical power to keep it running once the glow plugs have warmed it up and the starter has turned it over.

Or maybe I'm mistaken...but the owners manual specifically says you can't stop the engine with the key switch.

 

[dodge man]

On my BX turning the key off actuates a little solenoid that shuts off the fuel. There is a small lift pump that is electrical that keeps fuel going to the main injector pump on a BX, but I've read they will run without this pump, maybe just not very well. Other than the small lift pump, it doesn't take any juice to keep the engine running that I know of.

 

[jimmer2880]

I for one am enjoying this thread. All of my previous tractors, had a manual, cable operated air (I think) shutoff. My bx1830 has something that when I turn the key off, something shuts the engine off.

Once, I rolled one of the previous tractors before, who's air shutoff cable was frozen, and I had to climb back on the tractor-seat, while on it's side, hold the break and release the clutch to stall it.

I've thought about that many times and what I could do to shut-off my 1830 HST if the key didn't work. Without installing an air shut-off - I'm still at a loss.

 

[kuboman]

I'm a complete newbie with diesels, but when I turn the key to 'off' on my Kubota L2350 it doesn't do a darned thing. I have to reach down and pull up the fuel shutoff lever all the way to the top.

What could an electrical switch activate (or deactivate) to kill a diesel engine? A fuel shutoff? An air shutoff? Electrically activated compression release? What else? My little tractor doesn't have any of those things. There is absolutely nothing attached to my engine that uses electrical power to keep it running once the glow plugs have warmed it up and the starter has turned it over.

Or maybe I'm mistaken...but the owners manual specifically says you can't stop the engine with the key switch.

If you do not have a solenoid shut off then you must have a cable shutoff. Or sometimes the throttle lever is the shut off.:thumbsup:

 

[firemech]

I agree with those that say you need to shut the air off to stop a runaway diesel. As a retired mechanic from a fire department, all of our diesel fire trucks had mechanical (not electrical) air shut off plates or spring loaded b utterflys in case a truck at a hazardous material call started ingesting flammable fumes. From experience, the spring loaded butterflys worked the best as most plates were basically gravity operated (with air flow assistance) so would not likely operate during a rollover. One additional note however is that some; if running at speed when the emergency shutdown was operated would suck in seals or dislodge air intake hoses and render the shutdown ineffective. I think the CO2 extinguisher might be more effective as it takes the oxygen away without disrupting the actual air flow. Just my opinion
FIREMECH

 

[jagyzf]

Has anyone tried the CO2 proposal? At a high enough temperature even Nitrogen will oxidize in the presence of oxygen (thats where NOx comes from) so I would imagine that a screaming diesel running (rich) on its own oil would have no problem using CO2 as an oxidizer. CO2 works fine on combustion at lower temperatures. Remember that NOx is used as a performance booster for high performance engines.

I could see where plumbing an N2 cylinder directly into the manifold would work reliably, since there is no oxygen to dissociate. Probably a hassle obtaining one small enough though.

Say what???

CO2 is used in fire extinguishers due to it can't be used as an oxidizer and will displace the O2 in an area. It is also why EGR works at slowing and reducing the temps in cylinders. As another said NOx can't either, it is a nasty by product of high temp cumbustion

 

[Don87]

Thanks for the clarification and your opinion, are you sure I am the one not in the know?

How many class 8 truck engines have you worked on in the last 27 years of your life? :

I started working on small engines when I was 12, went on to motorcycles, cars, trucks, dozers, skidders. Held a Pa. Motor Vehicle Inspection License for 5 years before I went into logging, and have been driving tractor-trailer since 2001.

And as to your first question in this, It is not a matter of opinion, my dear fellow............it is a matter of fact.

Read post number 3.........follow the link provided..........and you will gain some valuable knowledge:thumbsup:

As has been stated many times throughout this thread, there are several types of 'shut-offs'.


A solenoid shut-off to stop fuel flow via the fuel pump, will shut off the diesel.

But if the tractor rolls, and the engine oil can get into the cylinders, you now have an unmetered, unstoppable fuel supply(til the oil runs out).........that is a runaway diesel.

 

[Baby Grand]

There are none so dangerous to themselves and the people around them as those who cannot accept that they may be wrong. I have observed this first hand on several occaisions and it always raises the hair on the back of my neck.
-Jim

 

[Don87]

There are none so dangerous to themselves and the people around them as those who cannot accept that they may be wrong. I have observed this first hand on several occaisions and it always raises the hair on the back of my neck.
-Jim

I been there also..........only once, but once was enough.

Dunno which scared me worse, the runaway diesel..........or the steer tire that blew on my rig at 70 mph on interstate 80, a few months back.

 

[JFS2295]

Never saw this thread during the years, but it's interesting. I've watched a couple of run-a-ways in my lifetime.

One was a just rebuilt 2 stoke Detroit. It was being started in-frame when the motor sneezed and started to run in reverse direction. That apparently just totally screws up the governor, or it had other issues. The mechanic kept trying to seal off the intake to shut it down but the material just kept blowing off. He was totally dumbfounded that pressure was coming out the intake. A shop foreman had grabbed a fire extinguisher and stated later he was going to shoot it into the exhaust since he realized what was happening, but the motor grenaded before he got to it.

The second was recent in a NJ Transit bus garage. A unit was pushed in with leaking turbo seals on the motor, but an inexperienced mechanic wanted to start to hear what was going on. Once he rev'd it up she just ran away. They shut of the fuel supply but it didn't matter. The shop just filled with dense oily smoke that smelled like burning rubber until the oil was used up. No one wanted to go near the motor while she was running.

And I've seen the aftermath of a Powerstroke with bad turbo seals.

The situation with the OP is a very rare instance, but the likelihood is raised with the new closed crankcase systems. As mentioned, all a diesel needs is some combustible material in the combustion chambers, and it's not particular if it gets there by injector or intake passages. Whether the combustible material is motor oil or released gases, the motors power and rpm are limited only by the quantity of material entering in through the intake passages. You can shut off all the electrical and diesel fuel you want, and you could even take an axe to the diesel fuel lines, but she is going to run. Totally ungoverned by anything engineered into the motor.

If you want to protect your 4 stroke diesel from the very, very rare run-a-way, the intake closure valve is the best solution. "Allie" my dozer over to the left has a singing Detroit 2 Stroke in it and uses an intake closure valve as it's shut off. Very simple; very effective.

Edit with picture of shut-off pull knob in the center of the dash.

 

[V1Rotate]

I agree with those that say you need to shut the air off to stop a runaway diesel. As a retired mechanic from a fire department, all of our diesel fire trucks had mechanical (not electrical) air shut off plates or spring loaded b utterflys in case a truck at a hazardous material call started ingesting flammable fumes. From experience, the spring loaded butterflys worked the best as most plates were basically gravity operated (with air flow assistance) so would not likely operate during a rollover. One additional note however is that some; if running at speed when the emergency shutdown was operated would suck in seals or dislodge air intake hoses and render the shutdown ineffective. I think the CO2 extinguisher might be more effective as it takes the oxygen away without disrupting the actual air flow. Just my opinion
FIREMECH

Has anyone ever used a Co2 extinguisher to kill a diesel?
Because of the huge volume of air that is ingested into the intake with the engine at high RPM, I suspect that unless you get 100% of the Co2 into the intake with no ambient air also being sucked in the engine will only be drawing in a partial mix of Co2. I think this might only slow the engine down and not completely kill it. Also, Co2 is extremely cold, I wonder about thermal shock to a hot engine.

 

[o2batsea]

While a runaway may be spectacular it doesn't mean the death of the engine as the OP found to his relief. Several of my off-roading acquaintances have rolled their trucks and had them run away with no ill effects save for the need to replace all the lubrication. If done often enough though it will eventually kill the motor as it gets starved for oil as it reaches the end of the event.

 

[Johnbro]

Say what???

CO2 is used in fire extinguishers due to it can't be used as an oxidizer and will displace the O2 in an area. It is also why EGR works at slowing and reducing the temps in cylinders. As another said NOx can't either, it is a nasty by product of high temp cumbustion

C02 is what you get when you completely oxidize (ie burn) carbon. Because it's completely oxidized, it's nice as a shielding gas for fire extinguishers or welding, or for adding bubbles to your favorite beverage.