Runaway multifuel 6/20/14

[ke5eua]

co2 will work fine no need to get expensive both displace air

True, military uses halon in all their wheeled and track vehicles that have fire suppression systems.

 

[MtnSnow]

Halon is no longer being produced and so it's getting harder to obtain. CO2 is the better solution for us average Joes. Cheap and easy to obtain.

 

[andy3]

Anyone decide to assemble a CO2 bottle into the fording hole yet? I came across some small bottles that could be used.

 

[rustystud]

Anyone decide to assemble a CO2 bottle into the fording hole yet? I came across some small bottles that could be used.
View attachment 502938

Now that is a handy size ! With a remote activated switch, it would work like a champ.

 

[andy3]

I was thinking a remote pull release valve on a cable like the air tank remote drain valves with a cable thru the firewall.

 

[Keith_J]

I understand the concept of using CO2, but, has anyone considered the number of cubic feet of gas needed to completely displace the O2 being pulled into the engine and that this flow will have to continue until the rotating mass comes to a full stop or they will just re-start?

Just a thought......

480 cubic inches, 240 per revolution as it is a 4 stroke. 3600 rpm so 86400 cubic inches per minute, that is 500 cubic feet. One pound of carbon dioxide is about 8 cubic feet so a one pounder needs to be discharged at 8/500 minute, roughly one second.

sounds like a five pounder is necessary.

 

[cattlerepairman]

Commercially, air intake shutoff valves are available (we have them on all of our fire trucks). Probably spendy, but you never know what you can find at a good truck salvage yard. They are usually spring loaded and deploy automatically (rpm sensor) and/or with a switch.
Look at these: http://www.amot.com/products/air-intake-shutoff-valves

 

[Squirt-Truck]

Keith_J
Check your math. They will be pulling roughly 500 CFM (just over what the air cleaner is rated) at that speed, and at 8cf per pound that is 62.5 pounds, and that assumes that the engine comes to a full stop in 60 seconds from that speed.

 

[Keith_J]

Keith_J
Check your math. They will be pulling roughly 500 CFM (just over what the air cleaner is rated) at that speed, and at 8cf per pound that is 62.5 pounds, and that assumes that the engine comes to a full stop in 60 seconds from that speed.

That is why I said a 5 pound extinguisher would be needed. If there is an intake butterfly valve, then far less would be needed as manifold pressure would be reduced. My TDI has such a device to prevent shut off shudder, works well to kill the engine too when I have had to override the electrical fuel shut off due to immobilizer malfunction (hot-wire to injection pump shut off solenoid, this is an electronic modulated version of the LDT/LDS injection pump).

 

[rustystud]

480 cubic inches, 240 per revolution as it is a 4 stroke. 3600 rpm so 86400 cubic inches per minute, that is 500 cubic feet. One pound of carbon dioxide is about 8 cubic feet so a one pounder needs to be discharged at 8/500 minute, roughly one second.

sounds like a five pounder is necessary.

What you need to consider is 1) The engine will not be going 3600 rpm. 2) When you shut-off an engine, it will slow down and stop much faster since the compression is NOT helping to turn the crank. Just for grins and giggles, go out and check your truck. See how fast it will stop turning after you shut-off the fuel. It is a lot faster then you think.

 

[Pugsley]

Combine the Co2 and stalling it with the clutch and you should be able to stop it really fast.

 

[Floridianson]

I have found when replacing the HH before you install it with the head in you hand turn it up side down and the control coller shoud move freely down. Then turn it over right side up and the coller will slide down again easley. I'm just throwing this out there but in the OP case maybe the coller was stuck in the up pisition when he installed the control assembely. Then when he installed the assembely the pin was under the coller and not in the slot causing it to be in high idle.
Myself when replacing the head as said double check that the control assembely is moving freeley without binding and goes from about the 4 oclock pisition (shut down) to about the 7 oclock pisition (high idle). I myself have left the shutdown cover off and can run the motor up or shut it down by hand. It has been said if the truck has been running the chance of the control assembely being not stuck today but stuck tommorow is slim. Seems the want to stick when they have sat way to long. Always make shure the when you install the shut down cover the motor is shut down and the cable control is pushed in on the dash so it will engage the assembely. We have talked about lots of way to stop a runaway but with the Deuce I believe if the control rod and assembely is working as it should you just have to pull the stop on the dash. When trying to start a truck that you are not shure that the shut down and control assembely is free and correct then take the time to remove the shut down cover (two screws) and double check all is free and clear to fire them up. As I said if we have control of the coller with or without the shut down cover being on you should allway be able to shut them down.
As for the open port on the air filter housing just run the correct size hose to the air compresser intake as per the TM.

 

[frank8003]

"As for the open port on the air filter housing just run the correct size hose to the air compresser intake as per the TM."

I am still seeking that TM mentioned.
I ask is that picture and information inside the TM’s or in a work order somewhere at the end of a TM?

 

[Keith_J]

What you need to consider is 1) The engine will not be going 3600 rpm. 2) When you shut-off an engine, it will slow down and stop much faster since the compression is NOT helping to turn the crank. Just for grins and giggles, go out and check your truck. See how fast it will stop turning after you shut-off the fuel. It is a lot faster then you think.

During a run-away as the original poster had happen, engine speed would be very high. The issue of fueling from lube oil would require choking or extinguishing with carbon dioxide.

 

[acesneights1]

Autopsy performed yet ?
I am curious to know if you lost any hard parts like I did.
I don't think runaway is something we have to worry about under common use. More of a "I just worked on the IP and probably screwed it up" scenario. I see no reason to need a truck mounted system. Just have a plan in place when firing up an unknown entity. I thought I did and my plan failed. Make sure your clutch is good....

 

[Floridianson]

Found it.

 

[bsorcs]

Interesting questions. Regarding CO2 delivery, at 3600 rpm air flow in would be about 8.33 cubic feet per second, so this would appear to be the maximum rate that CO2 would have do discharge from a container. A 5-lb cylinder contains about 44 cuft of CO2; venting at 8.33 cfs would empty the cylinder in about 5 seconds at 32 degrees F and 1 atmosphere. The cold venting CO2 would quickly start to drop the engine temperature and would also be expanding rapidly as it [CO2] heats up, so a slower delivery rate is feasible. Anyone have any idea how quickly a cylinder can vent? The net result would seem to be that a longer emptying time might be acceptable. Rustystud pointed to rapid slowing, so 10-?? seconds of CO2 delivery might be sufficient. It would interesting if someone out there with such a system in place had some idea of the numbers and posted a stop time, if such a person is willing to run a potentially pricey experiment!

 

[hklvette]

You need to displace enough oxygen to prevent the fuel (be it diesel or oil) from igniting, or at least enough that the weak ignition isn't enough to keep the engine spinning at high rpm.

 

[two.fiveM35]

There is all this talk about CO2, would putting it in 5th and stalling it not work?

 

[ke5eua]

There is all this talk about CO2, would putting it in 5th and stalling it not work?

One would think but at that rpm your more inclined to breaking something, although if it stalls the engine it might be worth it.

It is a good question if the input shaft can handle that shock speed like that or would it fail.