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Runaway shut off valve (positive air flow valve)

Will L.

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Engine run away is not something a lot of 6.2/6.5, dmax, owners face. But once someone faces it or something similar like WOT pmd or bad fuel shut off solenoid- it becomes more of a consideration. As soon as most people experience it first hand- they either mandate it on all their diesel engines or walk away from diesels forever. Anyone that watched a few YouTube videos starts thinking a shut off valve is a good idea. Then they search online to see prices that ends the theory.

I worked in fuel and oil industry where they are mandated where $2500+ fully automatic and certified unit can make sense even on a $20,000 or more engine.

I’ve spent time figuring out an affordable alternative to what is for sale, cable activated and NOT certified.
I haven’t found any for under $500, but could maybe get it together for half that retail.

Anyone interested? What pricetag would people go for on a cable activated one if I set up with a vendor to sell them?

It wouldn’t work with stock turbo hummers- need an inner cooler. n/a hummers could adapt to it. All pickups could adapt to it. There is a couple ways to make them, inline hose or upper intake mounted depending on intake you have and desire.

I don’t know if this is something that could be brought to market or not. I wouldn’t sell them direct- only through forum vendors. I am a firm believer in that. I haven’t contacted any vendor about this yet, want to know before wasting their time.

Please let me know good, bad or ugly. If anyone knows comparable cost units out there, please share. Could save me and vendors time and help everyone that wants to protect their engine and family at an acceptable price.
 
With 260,000 miles on my truck, most anything could happen. I`d Definetely be interested in installing one.
See if You can work up an approximate cost and I`ll go for it. I`d even be interested in paying before its developed just to help on the costs.
For some reason a run away engine has been on My mind ever since I got this truck. More like a nightmarish thought and I aint even the paranoid type, usually. LOL
 
@MrMarty51 be a bit before ready, but I will keep that in mind.
I’ll admit to being the paranoid type because I’ve seen a 6.5 and a cummins in person. 6.5 doesn’t go crazy exterior damage, just turns into a boat anchor.

This was all in my future to do list after my engine is built. One of the new members mentioned his engine rapping up got me to thinking of asking everyone this after I mentioned later he might consider a shut off valve.

On the Hummer forum A guy mentioned 6.5 not doing that and had them confused with an engine starting backwards, so I posted a couple videos. First one isn’t fair because it is the most spectacular one I’ve seen online with a full race Duramax. He would have had to had the intake mounted one I mentioned, not inline of a hose. Watch the video and you’ll see why. The other one was just cuz it was a 6.5 Hummer.


 
First 71 series Detroit I was operating on a hotplant, asked the trainer what is thes cable handle marked EMERGENCY SHUT OFF for ?
That was when I first heard of a diesel having a run away.
A situation I hope I never experience.
Another old timer mechanic told me that if the E shut down is used on the Detroit it usually destroys the seals in the super charger so those needs to be replaced before firing up the engine again.
I dont know if the same would be true on a 6.5 turbo after a run away and air intake type of a shut down.
I do believe that the air intake type of a shut down would be the better of the two options of it or fuel.
 
A cheap way is to start with a throttle body from a gas engine. Remove the return spring, modify the hookup side with a spring loaded solenoid, and you now have a cheap inline cutoff.
Exactly along the lines I was thinking. But after having delt with accidental engine shut off on the old two stroke diesels, the catch systems wear and can cause an accidental activation causing engine to die. This could be a bad situation so I simply want a pull cable. Complete driver control.

Mechanical cable so no electrical fault is possible. The high dollar units to be certified require replacing the electrical control assembly every 3 years in life critical applications but the cable activated ones simply require a test run and inspection.

As to required replacement in the Detroits- many of the engines dont have it as emergency, but as primary means of shutting off the engine. Just a cable and a push button. Only at overspeed situations does the seals get damaged, and actually quite often the bad seals leaking in the oil is what cases the run away. Much like a turbo leaking oil into the intake manifold. And often people say “Johnny pulled the shutoff and now I have to rebuild the blower!” When reality is the blower needed seals, finally leaked enough oil that only the shutoff saved the entire engine. And the mechanic has his cause and effect reversed.

And btw, those are just blowers not supercharger. The blower is required to move clean air into the cylinder and push out burned fuel/air. Since it is 2strokes, not one just to exhaust and another just to intake. When that device is installed on a 4 stroke engine that gets rid of its own exhaust and intakes its own air, then the “blower” charges excessive air into the 4 stroke engine so it becomes a supercharger as in extra-charger. AKA forced induction.

My intention isn’t to try generating an income stream (Although extra cash never hurts-haha). I really want to see a vendor that can fabricate build these as a low cost kit so more people can install them. I do have a bias towards them because once you experience it- it makes the importance much greater. And currently when anyone ever looks into it the only options they find are multi thousand dollar ones. The parts and a bit of labor could make a kit available for $250, maybe $200 even if done in some volume and be profitable for a vendor while making an affordable option for everyone.
Its like a manual waste gate controller for various turbos. Folks can diy them, but for a low cost a descent quality one can be ready made. I would think that same vendor could list them on ebay and make some cash to the masses that way.
 
A class We had on the 8.2, about tuning on the racks. The instructor told us that if the rack was not properly set there would be a run away condition. He told us to never install the air filter assembly and always have a piece of plywood at hand when first firing engine after setting the rack. He also advised us to NEVER PUT YOUR BUTT OVER THE INTAKE TO SHUT IT DOWN.
True story, He knew of a case where someone had done that. It did not turn out so well is what He said.
 
Only a few people interested in buying a ready made kit for the $250 range between TTS and hummer forum and no vendors asked so I’ll call marketability dead. So when my engine is together and i get to building mine, I’ll just show what I do so anyone interested can copy diy. Anyone that can’t DIY just ask and I will help best I can.
 
Interesting idea one of the guys had on the Hummerforum about using the chemical fire sticks to “put out” a runaway Engine. (There’s a YouTube video of Jay Leno using one if not familiar.)

Any one here have a test dummy engine they would hold at WOT while trying to see if one of these will shut off engine?

His comment quoted in box then my reply is below that:

Guinness44 wrote:
Element fire extinguisher: somebody needs to test this on a runaway. May be the large stick runs long enough..... (the company has not tested it for this, may be in Italy this is not a problem).



That is a cool idea because there are ones that don’t work by starving oxygen.

Oxygen starving ones like normal ABC units don't work because it is like having to put out a huge house fire all at once. Also the powder in regular fire extinguisher is going to destroy the cylinder walls and rings (seen that unfortunately).

A 6.5 liter means every 1 time the engine turns over all 8 cylinders it gulps 6.5 liters of air. 4,000 rpm for only 5 seconds is 2,166 liters (433 liters a second). Regular fire extinguishers just dont Supply volume fast enough. If the diesel has a true oil runaway they usually run 25% for first 5 seconds then up to 50% over top engine speed so 5,000-6,000 rpm for a 6.5. Thats why quick shut down is important. Time to get out, open hood, etc usually means pistons have hit valves for us because stock valve springs float at 5,000 rpm. I had to upgrade them on my race engines to withstand the 6,000 rpm at all.

But the chemical one with the smoke- idk if that would damage anything in the engine or not.
Also wonder- would it work through the air filter? Just pop off the mushroom cap and shoot it down the hole?

Anybody have a beater Diesel engine they want to try it on? Just need a diesel beater... wish I had the Mercedes still. That would have been a good candidate except I would have to vacuum off half of the extinguisher smoke to simulate proportional engine size since it was only a 3 liter.

This is a great idea- gonna post this on other forum too incase someone has a beater they plan on redoing. I remember when a couple guys tried forcing runanways on 6.2 because the block was cracked anyways.

Hey, ya sure you dont wanna out that 1994 n/a 6.5 for a new turbo engine? Haha.
_________________
 
I wonder about one or two of those big CO2 extinguishers that freezes everything they`re sprayed on ? They displace oxygen without the damaging results of other chemicals and powders.
Would need it or them mounted so they can be fired off quickly without opening the hood to save an engine, directly into the air cleaner.
Good old carbon tetrachloride fluid would do it too, just dont breathe in the crap, CO2 is the same though.
The DOT, in the stockroom was a jar with some liquid in it. I asked the stockman whats in this jar, he did not know. I unscrewed the ring, lifted the lid, took a sniff and my breath was cut off immediately and it took quite a while before I could catch another breath. I never smelled a thing so i do not know what flavor it may have been but I am guessing it may have been carbon tet for refilling them old extinguishers. Thats an experience that I never wanna ever go through again.
 
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Have to figure the cost of them, how to mount them, figure the deploy control. But most importantly, have to know it has enough co2 in there and it can deploy fast enough.
Keep in mind the volume dumps quicker at first and slow at the end. Seeing as how the cheapest 5 pounder (i dont think big enough) co2 is about $170 before any deployment control- no way it could be cheaper imo.
 
Just curious if a inline throttle body with mechanical cable operation and same OD as the ID of the turbo hose can be obtained. Set it up so it is normally open the pull shut with a cable.
Maybe I will go scrounge the auto salvage yard and see whats out there. Oh wait, its cold outside. :banghead: LOLOLOL
Maybe I will wait until it warms some. :woot:
 
Exactly the game plan minus the junkyard. I planned on buying returnable chineseium throttle bodies until settling on a descent one. 2 1/2” is 64mm, 3” is 77mm, throttle bodies are listed in mm. Rounding up/ go to next common larger size.
Make sure the butterfly opens to perfectly flat and make a detent for it to rest in that position so the cable does not hold the load.
Make sure the “idle” position closes 100%
Kill any external “vacuum” ports unless you want it as a boost gauge or air temp port.

For inline, you’ll need to weld 2 new flanges on, or use your new flange at the downstream side making a large contact area and bead to ensure the downside hose can not blow off under high pressure. Actually having a weak link at someplace upstream although could be annoying is smarter so a 6,000 rpm runaway building say 35 psi boost will never blow off that all important downstream connection. Buying a multi tooth king nipple to use may be better than a pipe with a single groove. They are hard to install but usually require cutting off the hose to remove.

Another option is using the flat top plate design and Bolting on the throttle body directly to it. I’ll find a couple possible examples from fleabay and edit post shortly.
 
25BCBB9B-6B60-4E9D-83D5-EECC275683B5.png
So this could be one used for inline. Weld on a chopped king nipple to the back or make a bolt on plate with king nipple for the back.
The front is very short and could cause easily blown off hose under boost, so welding addition onto it maybe needed.
Note the vacuum port as mentioned. I really doubt accurate boost would be read as it is in a peak flow area and temp readings would be altered too from airflow, so plugging the this one would be required.

Removing the spring to auto close definitely required.

This same unit could be mounted to a flat plate that bolts directly to the lower intake manifold and have the hose from the turbo feed directly to it.

Want high performance and mega flow with a 4” hose coming off your turbo? 102mm throttle bodies are out there too.
2C25CD68-CFD8-4C2B-98FE-4661EA11ED33.png

This one is at an amazing price about half that of most 102 for sell. So I would expect to return this one after inspection, but who knows?
Again notice the tiny area to attach the hose. On a plain gas engine, there is vacuum not pressure, and I will
Also tell you from Ownership of LS engines, the intake piece just popped off too easy on these. Watch professional mechanics work on them and they just push down on them to remove bever having loosened the clamp even because it saves time. Adding to this one is a flat requirement.

Was also thinking a vendor might have gotten ahold of seller and bought 20 at a time for volume discount with these and the cables to help his profit.

AVOID cheap cables. They create problems, rust solid, allows dirt to build up inside, etc. example:
13825881-66F6-4EFD-B1FA-94AFAC3966F2.png
A quality cable will last a lifetime and be reliable. This is a pto control cable, I have installed a couple hundred of these and they took abuse and outlast the pto. Doesn’t need to be this brand, but at least match the quality and being a sealed cable is always best.
FB725237-0675-40C4-B62F-8D8D8D14E926.png

Note this does not come with the mounting hardware, handle, end attachment unit.


A factory throttle cable with mount could be a good option also, you just need to do some fabrication to make the pull handle.

Make sure the cable is pushed in for normal operation and has to be pulled out to kill the engine.
 
I got a pm asking about the plate mount.
LeroyDiesel and Quadstar sell a really nice one with 3” piping from plate to turbo location. Look at that for example or buy a throttlebody and pay them to build it into their design maybe?
Mounting the cable to the plate might be easiest method.

And for the forum sponsors on this page, one hummer owner on other thread spoke up and said he is willing to pay $500 for one...maybe a short run could be worth it then build after payment only in future.

That flat plate with welded tubing is exactly how i did my twin turbos back in the 90’s btw.
 
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