Diesel Runaway Description:

[MIDNIGHT RIDER]

I'm not disputing this, I am curious how does oil burn fast enough to get the engine to 10k rpms?
Also, what kinda diesels run to 6k on fuel? The highest I've seen is 5200rpms.
Of course I don't mess with really small diesels that often.

Dp

The big prime-mover engines, both two- and four-stroke often idle at about 300-RPM and maximum operating RPM is about 900, maybe 1000, just about where any run-of-the-mill small diesel would only be idling.

The Bosch VE injector-pumps have a wide assortment of governor springs, ranging from less than 2000-RPM to over 6000-RPM.

It is not at all impossible for the smaller diesels to rev just as high as a gasoline engine.

On the other hand, considering one of those big GEs, ALCOs, HERCULES, EMDs, DEUTZ, or whatever those tugs are powered with is a different story.

 

[MIDNIGHT RIDER]

When I worked for a heavy truck manufacturer, we installed on any fuel tanker truck a system which mechanically shuts off the intake air if the engine RPM exceeded a certain value (usually set a couple hundred RPM above engine redline). This in case the truck was in an area with sufficient fuel vapors (such as from a large gasoline or propane leak) which could cause an engine runaway.

Most of those systems consist of a guillitine cut-off somewhere along the intake plumbing which functions exactly like a simple wood-working dust-collector cut-off.

They are standard equipment on crude-oil tankers due to the presence of natural gas that is always around crude-oil tanks and wells.

 

[redmondjp]

This has been a very educational thread!

I'm really surprised that at those diesel truck & tractor pulls that they don't require some sort of intake air shutoff mechanism, or maybe some other means of forcing a shutdown such as a CO2 or N2 injection system on the intake - this would starve the engine for oxygen and cause it to stop running(and would be really easy to install and remotely activate).

On a number of those U-tube videos, you can hear guys talking about the fact that they have activated the remote shutdown, but of course that has absolutely no effect when the engine is running on its own oil! Proof again that what works on a gasser doesn't always cut it on a diesel . . . D'op!

Oh, and the number of guys just standing there right on the side of the engine compartment while the engine is in runaway - well, that's just natural selection at work I guess! If something is going to fly out, it's going to come out the side. Sitting in the cab isn't the best idea either, in case the flywheel, clutch or torque converter decides to let loose at some way-over-redline RPM. YMMV

 

[DeepRoots]

On the other hand, considering one of those big GEs, ALCOs, HERCULES, EMDs, DEUTZ, or whatever those tugs are powered with is a different story.

so how fast ya think the ole Mak would spin before it would pop? (and yeah, thats me by the pump motor)

You must be registered for see images attach

 

[rjjp]

I'm not disputing this, I am curious how does oil burn fast enough to get the engine to 10k rpms?
Also, what kinda diesels run to 6k on fuel? The highest I've seen is 5200rpms.
Of course I don't mess with really small diesels that often.

Dp

I was speaking of the small diesels in some of the foreign cars and such... BTW driving those little SOBs blows, no torque.

 

[FordGuy100]

I was speaking of the small diesels in some of the foreign cars and such... BTW driving those little SOBs blows, no torque.

They have more torque than gassers of the same cubic inches. Cant dump the clutch and go like an IDI, but dont have to give em any throttle to get going.

 

[MIDNIGHT RIDER]

so how fast ya think the ole Mak would spin before it would pop? (and yeah, thats me by the pump motor)

You must be registered for see images attach

Thanks for the picture.

That makes what I thought were big locomotive engines look like toys.

 

[OLDBULL8]

Why is that big tire and brake drum on top at the rear, shouldn't it be underneath?

 

[MidnightBlade]

Killing a runaway is about the only thing a phonebook is good for anymore.

When my Diesel instructor was in the U.S. Navy he had one of the smaller diesels (land vehicle) run away. His first instinct was to slap a phone book over the turbo (thickest thing handy). Well, the engine was spinning enough RPM to suck the phone book through the turbo

 

[gatorman21218]

http://www.youtube.com/watch?v=3NRaqgab0_w

heres a 4-53 running away. the guy stopped it in time though

 

[redmondjp]

http://www.youtube.com/watch?v=3NRaqgab0_w

heres a 4-53 running away. the guy stopped it in time though

And is #$%$%^ lucky to still have all of his fingers!!! A phone book, a piece of 2x6, ANYTHING would have been safer than using his hand . . .

 

[FordGuy100]

And is #$%$%^ lucky to still have all of his fingers!!! A phone book, piece of 2x6, ANYTHING would have been safer than using your hand . . .

Probably popped some darned blood vessels!

 

[rjjp]

They have more torque than gassers of the same cubic inches. Cant dump the clutch and go like an IDI, but dont have to give em any throttle to get going.

, I haven't had any experience with any of the new ones (other than prototypes) but the ones that I've played with were about like a Honda BigRed towing 2000lbs, only slower acceleration. Yes for those who are curious I have towed over 1 ton with a three-wheeler, it's not that bad, until it starts sloshing around.

 

[sassyrel]

I have seen a cummins 350 run away one of the mechanics at the shop i worked at was playing with the linkage on the pt pump and started it with it unhooked . it took off we finally got it to shut off stuffing dirty uniforms around the air cleaner the eng was okay . at one of our other yards they were replacing a blown turbo on a mack e7 300 and they didnt clean out the charge air cooler . they were revving it up with cab over well it took off they all ran after that it needed a new motor bent every rod and smacked almost every valve . has anyone ever seen a diesel run backwards.

yup..had a dd run backwards on me,,pulling a sharp grade in low,and it killed,then instantly started backwards...smoke out the intake!!!

 

[Dieselcrawler]

Had a cat 3406b run backwards once. The idle switch for the Jakes wasn't working. Jakes came on all 6 cyls at idle, bringing the motor almost to a stop before I got them switched off. Motor returned to idle but sounded weird. Let the clutch out in first and backwards I went. Then quick shut it down before lack of oil caused any issues