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Runaway shut off valve (positive air flow valve)

MrMarty51 said:
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.
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That'd be ONE GIANT ASS TURBO HICKEY!:D:Do_O:hilarious::hilarious:😄😄😆😆🤣🤣😂😂🤪
 
Will L. said:
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.
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After I built mine I found BD Diesel has a few options in the $600-$900 price range. Several distributors sell them.
 
I realize it's most certainly a panic reaction and there wasn't time for a thorough well thought response, but at what moment did the guy think to himself "I guess I should probably sit on that gaping hole sucking lots of air over top of a loud spinning monster that is wildly unpredictable, to say the least"??
 
Ive seen a guy try using his hand over the turbo. Then reached in with the other hand to free it. He went from $80k a year driving semi as owner operator to $30k a service writer who used a keyboard instead of a pen…

Bad part was I was coming back with a piece of 1/8 plate. He just wouldn’t wait.

I installed solenoid door poppers on his pickup like ya do on a hot rod with shaved handles. Also swapped his 4 speed to an auto for him. Right hand has index and most of middle finger. Left hand he lost 3/4 thumb and all pinky.
 
A little levity for a serious subject. Will, I apologize for the derail this will inevitably cause.

I had one on my truck when I first bought it. Research showed it could be had for about $25 from SS Diesel prior to 2007.
It was an unknow feature built in to his early versions of a ”Cold Air Intake” only it wasn't supposed to be an air cut off device as it was the air filter.
(Old picture of the motor after I bought the truck off Flea-Bay in 2007. Note, the 'remote PMD Cooler' on the intake. I've learned a lot over the years.)
20070131 Motor.JPG


Plus, when it went 'off script,' it wasn’t command activated. At any random time the glue holding the metal cap on the cone portion would fail, the metal cap came off and blocked the turbo inlet. I got lucky and it just perfectly sealed the inlet like a bottle cap.
Filter-SSD Fail1.JPGFilter-top1.JPG

Others weren't so lucky as the metal went edge first into the Turbo's impellers giving one an excuse to upgrade to a “Wiz Wheel.” Not the 'spirograph' etching from the center shaft. I was very VERY fortunate. Yeah, a perfect fit and seal that had me chasing 'stalling for over a month. Could have been worse.
Filter-Top center.JPG



Back to more serious discussions....
 
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For a first time startup when a question such as this looms in terms of a freak chance and possibility, what is it someone should have in place? Is a piece of lumber in order to cover the opening? Does it need to be a thick piece of rubber belting so it somewhat seals?
 
It doesn't have to be perfectly air tight. A piece of 4"x4" ¼" plywood is sufficient, you just want something that's rigid enough that it doesn't deform and contact the compressor wheel blades. It's not like it's sucking in 100,000 cfm and will suck in loose objects, pets and small children from 5' away. You just want to choke off its supply of air for combustion.
 
SnowDrift said:
For a first time startup when a question such as this looms in terms of a freak chance and possibility, what is it someone should have in place? Is a piece of lumber in order to cover the opening? Does it need to be a thick piece of rubber belting so it somewhat seals?
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An 8.3 Detroit class. The instructor said we should have a piece of plywood handy just in case.
He also mentioned that the plywood should be just slightly bigger than the intake so that it dont get hung up on any obstacles but big enough fingers dont get slammed between the intake and the plywood.
I feel it would be good to have the plywood just slightly bigger than the intake, and, a set of handles on the outwards side to keep fingers out of harms way.
 
If you have an exposed air intake, a plastic bag over the filter would do it.
By the time you:
a. ascertain what's going on [runaway motor],
b. un-shat yourself
c. found the tools,
d. got the band clamps off while shakin' like a leaf,
e. get the air intake off the front of the turbo
f. while on the side of the road....
Might as well just go on line and find a deal on a new engine.
 
If one would build such an apparatus to install and make a permanent fixture for future emergencies. which would be the better placement (for the 6.2/6.5 engines) a throttle plate mounted on the intake between the turbo outlet and intake manifold, or mounted in front of the turbo inlet and air filter?

I am thinking about this for my truck, but trying to decide which would be 1. more effective and 2. the less likely chance for the turbo from blowing out / sucking out the oil seals.
 
@dbrannon79 immediately in front of the turbo intake, so that the inlet hose from the air filter can't collapse and possibly be sucked in or fail and still allow air in to continue feeding rhe run-away. Look at some of those built diesel sled pullers. That guillotine-looking device mounted right in front of the turbo(s) is(are) the emergency intake air cut-off(s) to prevent runaways
 
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SnowDrift said:
Closest you could get to the air getting sucked into the engine would be best - post turbo. For the most practical place, it's likely going to be pre-turbo.
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No. It is MUCH easier to cut off a vacuum air supply (pre turbo) than it is to cut off a pressurized air supply (post turbo), not to mention that under extremely high boosts during a run-away you also run the risk of blowing out the guillotine blade and thus not cutting off the air supply at all. Then there's the small fact that the cut-off device will leak slightly and if there's pressurized air flowing through it in the "open" position, then you'll have a constant boost leak. If on the intake side of the turbo, that miniscule leak is meaningless, as it's the sudden cutting off of the intake air supply that immediately chokes off a run-away and stalls out the motor.
 
SnowDrift said:
So a piece of wood here is not the right place?
View attachment 82330
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If the turbo to upper intake hose wasn't there and you were just doing a "let's fire 'er up and see if/how it runs before I put everything back together (like putting back on the turbo) run", yeah that would work fine.

Now, if everything was in place, like the turbo so you didn't have exhaust and extreme noise dumping out the turbo pedestal on the P.S. exhaust manifold, you'd want the air filter/CDR hose duct off so you could block off the compressor intake on the face of the turbo to kill the engine. Thatxs how the racers/pullers do it, with a guillotine-type cut-off valve right in front of the turbo(s) intake(s). Of course, if a nitrous backfire blows off most/all of the intake plumbing during WOT, ALL bets are off on stopping a run-away!
 
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