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Mechanical Killswitch

dragogt

dragogt

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Does anybody know of one for the 6.2/ 6.5? Tried a search but nothing came up..
 
I have heard that if you work near oil rigs it is a requirement to have so they are out there. If I remember it has something to do with a butterfly valve that cuts air to the engine and is placed between the turbo and intake.
 
This is a good topic. I've heard of a diesel 'running away' and the thought of it just gives me the heebee jeebees.

I mean, a governor or a fuel cutoff will do notta in this situation.

Grenade.
 
Its called the igntion switch :)

The thing cannot absolutely not inject fuel with the ignition off unless you bypassed the ignition somehow. The PCM, PMD and IP are all elecric and all needed to make the IP actually squirt.
 
buddy said:
Its called the igntion switch :)

The thing cannot absolutely not inject fuel with the ignition off unless you bypassed the ignition somehow. The PCM, PMD and IP are all elecric and all needed to make the IP actually squirt.
Click to expand...

But what about a db2?? No PCM or PMD....
3500GMC said:
We're talking the AIR being the FUEL...

No switch is going to save your ass with a diesel engine.
Click to expand...

I was actually referring to fuel, I've seen one try and run away; Boss choked it out with a wet rag... iirc (its been about 7-8 years now)
 
Air isnt fuel, unless youre putting some sort of fuel in the air. The only way the ignition switch isnt shutting down a EFI 6.5 is if you got loads of oil in the intake or putting propane or something into it.

Do you expect to have that issue?

The runaways people talk about with PMDs and IPs is immediately resolved with the ignition switch.

For a DB2, the fuel shutoff also runs off of ignition power. So unless something is messed up it shouldn't be able to run away with no key on either.
 
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What they mean by the air being the fuel is say at a gas compressor station a pipe breaks. There is no other way to shut off a diesel engine.

Many oilfield companies won't let a diesel truck on sight without a emergency shutoff.
 
Yessir.

Even large amounts of blow by can force a diesel engine into a run-away situation. Let alone a gas well venting off.
 
If thats whay you mean just say that. Thats not air, that fuel added to the air. No need for everyone to not understand their 6.5 can't runaway in their driveway if they just shut off the igntion. Blowby isnt going to be enough to sustain an engine without fuel from the IP, but for a couple chugs after shutdown maybe.
 
Well I knew what they meant. lol

If there is that much blowby that a runaway could occur, might as well let it. A rebuild is in your future anyway.:hihi:
 
I understood 3500s point, but it wasnt clear. I didnt think it was what the OP was asking about, and it wasnt. So everyone should realize if you shut your ignition off the IP will not be able to inject fuel, unless someone has bypassed power on stuff. Some Toyota owners could have used that lesson.
 
The OP was asking about a MECHANICAL kill switch. And when dealing with an 'air is fuel - fuel is air' situation, ... there is only two solutions. Stuff a rag in it, or let it grenade.

Or get a 'valve' like mentioned earlier.

edit: okay three solutions.
 
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Yep, I just wanted to make sure the OP and everyone understood that a mechanical kill switch is completely unnecessary unless youre in that one situation where you are in unbreathable environment, that is filled with gaseous fuel from a burst pipe.
 
buddy said:
Yep, I just wanted to make sure the OP and everyone understood that a mechanical kill switch is completely unnecessary unless youre in that one situation where you are in unbreathable environment, that is filled with gaseous fuel from a burst pipe.
Click to expand...

I agree, but I dunno about the unbreathable part.

Fact is, diesel engines have, can, and will run away when situations are 'right'... Or WRONG...:eek:
 
buddy said:
For a DB2, the fuel shutoff also runs off of ignition power. So unless something is messed up it shouldn't be able to run away with no key on either.
Click to expand...

That something that would be messed up would be if the DB2 is messed with(top cap wise) by someone that does not know what they are doing and the cap is re-installed incorrectly. If this happens you basically jam the metering valve wide open with the leg that comes off the solenoid. In this case, no key will save you. The engine will continue to scream away even if you disconnect the batteries and throw them across the yard. The only way you'll stop a 6.2 or mech injected 6.5 in this case is to suffocate it, or let it go bang.

If one lives in an environment that is at risk for a fuel source being in the air then an air guillotine valve is not a bad idea. It's cheaper than a new engine that's for sure.
 
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