I'd guess the pathology of a 7.3 runaway could go something like this...

1. Piston rings on their way out.
2. Fuel which doesn't atomize hits cylinder wall, escapes past ring into oil sump.
3. Oil level increases and becomes fuel / oil mixture.
4. Oil / fuel mixture gets back into cylinder past ring into combustion chamber while running.
5. Things go downhill from there.

In this case it wouldn't matter if HEUI's were not powered as a fuel source has a path of entry into the combustion chamber.

I've read about it - don't remember where and not claiming it was a 7.3 - but thankfully never lived it.

Suffocating the engine probably not an option if driving.

The only thing I could think of for an E4OD truck would be to mod it so you could lock the TCC (easy) and also force both shift solenoids into the 4th gear position (more difficult but from what I've read, possible). Then maybe you could stall it out with the brakes.

 

They don't like you Tom

 

I was at the diesel truck pulls this weekend, and one of the vendors had big turbo there that had a slide gate attached to a spring on the intake side of a turbo. Im guessing that is to shut a runaway down quickly when at the pulls.

 

i also have over 2 million road miles driving experience Bill.

 

Yea I've seen those are the really big bad drag/pull trucks! Like the ones where the 'plastic' or fiberglass body pops up like a hood to expose the giant frame/engine.
Those trucks have like an 8" turbo inlet lol.

 

It's good to hear from those that actually saw a 7.3 run away. I was always told, and always believed it wasn't possible.
Hope I never find out firsthand myself.

 

Not exactly "good" to hear (not for them, anyway )... but yeah, forewarned is forearmed. Maybe it's time to slide a clipboard under each driver's seat....

Hmm, is this another reason to do the CCV mod? One less way for the engine to vampire-drink its own oil?....

 

Correct. What you saw on the inlet of that turbo is an air shutoff. Run a cable into the cab of the truck and pull it to close the air shut off if needed.

A lot of pullers are also required to have a fuel shut off and it must kill the engine when tripped. The fuel shut off gets connected to the sled so that in the event of a breakaway, the fuel shut off gets pulled and the truck dies. This is tricky on a 7.3 b/c it will run without the fuel pump even running. So, put a switch on the fuel pump in the cab and connect the fuel shut off to the IDM. So now, if the fuel shut off gets pulled, it will kill power to the IDM and kill the engine. For tech inspection where they are listening to see if the fuel pump is running with the fuel shut off pulled, simply turn off the pump from inside the cab. lol

Another safety rule is cross bolts in the downpipe close to the turbo and exhaust must exit straight up or down. Both of these rules are to protect spectators in the event of a failed turbo where the turbine wheel shatters and exits the exhaust pipe in lots of little, sharp pieces. This happens more than you would think it does.

 

A few years ago I was talking to a guy at the end of the track, about 60 feet off to the side of the 300' mark, behind a big steel dumpster. A tractor took off from the starting line and only made it 50' or so before puking a turbo. The guy I was talking to got hit with a chunk of that turbo. How it made it that far and behind the dumpster is beyond me.
You definitely have to be paying full attention at these events.

 

I was just kiddin.........I like you Tom

That's a LOT of miles.

 

that is also why i like this new job where i am semi retired.
i went from 700-800 miles per day to 400-500 miles per week.
the past year has been a dream. granted i also went from over 80 grand a year to under 20 grand a year, but everything is paid for so i just watch what i spend and i am golden.

 

Sounds like FTE needs to start paying our moderators a little bit. Now THAT would be a gravy job for ya. Drop the ban hammer about once or twice a month and spend the rest of the day BSing with the coolest group of guys that you know, yet haven't met face to face. HA

 

Yeah!....What he said!

 

It would be so easy to work on the engine with the whole body in the air. One reason why I like lil Pete, the little big rig. I want to build one of those someday. Travis thanks for filing us in on the huge turbo, and pulling info.

 

In the case of a runaway with the 7.3 while I'm behind the wheel, I think the first things I'd try doing are:

Activate the exhaust brake switch (EBPV mod) which should restrict the engine
Activate the torque converter lockup switch (normally used with the exhaust brake)
Make sure transmission is in "D" (and "OD")
Apply brakes
Turn off key

Hopefully this would stop the engine (and probably damage the torque converter too).

If that doesn't work, I'd try putting something over the air filter. That's about as close as I can get to shutting off the air intake without cutting into the air cleaner hose system somehow. This approach can be hard to achieve if the runaway comes while you're in the cab and trying to stop the engine in other ways mentioned.