Engine/Transmission (1994 - 1998) runnaway cummins help!!!!!!!!

[bdcraig]

All this started when I put a new headgsket on my 2500. My truck became hard to start and had a lot of white smoke after the headgasket job. So having no history of this truck(I bought it used with 230,000 miles) I decided it was time to time it fix the KDP and an oil leak. Got it back together today and it was very rough to start the first time. Would occasionally idle up on its own. Sounded a bit different. #1 inj line was putting out more fuel than the others when the line was cracked. So I checked for leaks while it idled for 5 minutes or so when I decided to check the low idle. I then gave it throttle to about 1000 RPM and it took off on its own, WOT and then some. I shut the key off no luck. Then proceeded to pull the fuel shut off down by hand I even yanked the throttle linkage apart, but no luck. I then decided to loosen the banjo bolt but took at least 2 to 3 minutes to locate the my 3/4 wrench(it was hiding). Thankfully that killed it, temp was red hot as the theromastat was slow to open. So what happened? Did something brake in the govener? Sorry for being long winded.

 

[tp0d]

Next time you have a runaway, pull the air hose off the turbo and cut off the air with something rigid (piece of plywood, thicker metal) A rag/etc wouldnt be too good of an idea...



Are you sure you had the fuel shutdown solenoid fully closed? That would do the same thing as pulling off a banjo. Usually a runaway isnt caused by fuel, its oil. But hey, anything is possible. Did you see rpms past 3500?



good luck



-j

 

[bdcraig]

Don't know what the RPM's were but by the sound of it I'd bet they were to 3500. Yes I lowered the fuel shutdown by hand. I turned the key off and that didn't kill the engine so did it manually and nothing. Yes after it was over I thought of shuting down the air supply but in the heat of things fuel supply popped in my head. I'm thinking something in the govener is broken and whatever it is is also linked to the kill rod that the fuel shut down is connected to. I need to see a good picture of the internal workings. Piers has one but it doesn't show enough.



Brian

 

[TEasley]

Brian; My only experience with runaways was on big rigs in the oil patch. The only way to shut them down was to pull the emergency shut-off which cut off air to the engine. Sometimes it was caused by methane in the air, sometimes by lube oil getting into the cylinders. Both causes did not respond to anything you did to the fuel system because they weren't running away on diesel fuel. That's also why the governor didn't have any effect. It was common enough that they all had the built-in emergency cutoffs, but it would still scare the crap out of you.



Just a thought, but I wonder if lube oil from the compressor bearing might be getting sucked into the compressor ?



It seems unlikely, but the replaced head gasket is coincidental.



Scary stuff. Good luck, and for sure let us know what you find, Tom

 

[KLockliear]

If the rack is full forward, the fuel shut off solenoid won't stop the fuel.

 

[bdcraig]

I'm going to check everything out today. Maybe it is just quincedental that it happened after the head gsk job. I guess I can look on the bright side, if it hadn't popped up a big oil leak from the front seal I probably would have drove it longer before doing the timing. If that had happened I could have been in town in traffic when it took off and then we would have seen how quick my reactions were. Sometimes bad can be good. Well I 'll let you know what I find today.



Brian

 

[Timebomb]

If the rack is full forward, the fuel shut off solenoid won't stop the fuel.

Yep. . Shut off limits rack travel and if the rack is allready foward it can't stop it.

 

[bdcraig]

Today the fuel shut of is working. With the key on I can lift it up and it will hold till Iturn the key off. So what ever was stuck is now free. No oil in the intake but we kina figured that. Everything appears to be ok looking in the govenor housing after pulling the torque plate. Does anybody have any good pics looking down at the gov housing from the top. Maybe one with the gov forward and one with it back, just so I can compare. Also explain to me the rack and what I should be looking for out of the ordinary.



Thanks Brian

 

[bdcraig]

Well I found out one problem. Some how I got the delivery valve in upside down. Still not sure how I did that but I did. That explains why #1 inj was putting out way more fuel when I cracked the lines. Could this have caused the runaway by putting fuel in at all strokes. Still doesn't explain why the fuel shut off didn't work, unless when I gave it throttle the constant fuel shot the RMP's up so much that the gov got stuck thus not allowing the shut off to work. Any ideas? I'm heading to the farm machinery show tomorrow and will have a chance to speak with someone from Shied hopefully. Also the DV holder is scratched and causes the valve to stick. Any body have a spare holder?



Thanks

Brian

 

[bdcraig]

We'll I got it figured out. Yep I put the delivery valve in upside down and screwed it up. Anyway a piece of the delivery valve broke and went down into the helix and then got stuck in the rack and caused the rack to stick and the truck to runaway. Now I'm looking for a cheap 160 pump. I may have one located, but this is still a costly screw up. That'll teach me to get in a hurry and not double check everything. One thing for sure is I'll never install a delivery valve backwards again. Learn from your mistakes.



Brian

 

[supersonic]

You should be able to get it fixed cheaper than buying a used pump.

 

[bdcraig]

Core price is cheap enough. No more waiting to get it back running and I;ll have a pump for the future.



Brian

 

[TJHenderson]

Hey just to help out, when I was working for gm. I was putting inspection cover on 6. 5 pump. started truck and off to the races we go. I also tried to kill fuel, to no avail. But the good thing is the next time (hopefully never), You will now to suffocate the engine. But trust me even when it happens a second time, it is still scarry. When the school bus driver pulled into the lot at are shop, (school bus mechanic now. ) I was like crap and what and I pulled the air cover off, and used a clip board or two. But these things have other air inlets, I was told. The best thing to do is try to take Turbo pipe, or hose at turbo off, and cover it with flat, thick, and solid object. Make it large enough to keep fingers away, Turbo can turn into a blender at that speed fast. And remember also when working on the engine you have that choke plate with you just incase. TEasely has it made with the kill lever. But like I said hopefully it never happens again for you, everybody else, and myself.

 

[MMcCallie]

Brian,
I sent you a PM about a pump.
-Matt