Engine/Transmission (1994 - 1998) 97 2500 4X4 diesel will not shut down/turn off

[25004XINGA]

New to all of this, so your patience is appreciated. My truck has 231K and is in good mechanical shape. A problem of some concern has shown up in the last 1000 miles. If I run the truck form point A to point B, let's say 25 miles, the engine will shut right down after I put it in park and turn the ignition off. IF I run the truck say 50 miles, and shut it down, it will not shut down, EVEN after I have put it in park, turned it off, and taken the key out of the ignition--until approximately 10 seconds elapse. Seems like the longer I drive the truck, the longer it takes to shut down after I have taken the key out. Last weekend, I did a round trip to Savannah, Georgia, and after a stop at each end of the trip, it took approximately 25 seconds to shut down each leg of the trip. This has me very spooked. I am afraid that in the worst possible circumstances, the truck will not shut down at all. Any help and direction here will be greatly appreciated. Randall, Oxford, GA

 

[Killer223]

does it maybe have a turbo timer on it? else i'd check electrical for the fuel solenoid. could be a partial run away. i think the turbo oil seal if the likely cause of that.
Other experts more than I will chime in soon.

 

[25004XINGA]

does it maybe have a turbo timer on it? else i'd check electrical for the fuel solenoid. could be a partial run away. i think the turbo oil seal if the likely cause of that.
Other experts more than I will chime in soon.

Thanks Killer223. No turbo timer that I have any knowledge of. Entire main engine mechanicals are original OEM. I did change the fuel shutdown solenoid and relay (parts from Geno's) last summer. Have changed belts, water pump, and other standard maintenance parts. KDP was dealt with by me in 2010. No electrical changes or add-ons that I know of. Thanks again!

 

[25004XINGA]

Thanks Killer223. No turbo timer that I have any knowledge of. Entire main engine mechanicals are original OEM. I did change the fuel shutdown solenoid and relay (parts from Geno's) last summer. Have changed belts, water pump, and other standard maintenance parts. KDP was dealt with by me in 2010. No electrical changes or add-ons that I know of. Thanks again!

Kind of re-thinking the question: what is it that actually tells the engine that it is turned off? A ground from the ignition switch, an ignition switch terminal to the PCM to ground?

 

[GrantP]

Make sure the shutoff solenoid moves freely, it may be sticking or in need of replacement. It's really a simple fix.

Next time it continues to run, pop the hood and pull down on the solenoid to shut it off.

 

[GAmes]

When you turn the key off the electrical circuit to the hold coil of the FSS turns off the and FSS spring pushes the plunger down which rotates the lever to the fuel off position. The first thin I'd check is a binding FSS plunger. There is also the possibility your starter contacts are worn, but I've never heard of them only causing a problem after the engine gets hot.

http://www.fostertruck.com/faqs/

http://www.cumminsforum.com/forum/94-98-engine/569868-fuel-shut-off-solenoid-fss.html

 

[BigPapa]

I agree with Gary and Grant, make sure the solenoid plunger and linkage moves freely. The most common issue is the boot coming apart and mucking up the works. You can run the solenoid without a boot, mine hasn't had one for SEVERAL years and hundreds of thousands of miles. Still the original solenoid from '95. DO NOT lube the plunger, make sure it's clean and dry. DO lube the joint at the end of the plunger rod. I'd also swap the relay in the fuse panel with one of the others and see if it makes a difference.

 

[crabman]

Fuel shutoff solenoid explained:
http://www.cumminsforum.com/forum/94-98-engine/569868-fuel-shut-off-solenoid-fss.html
Edit:
Same link as above.

 

[25004XINGA]

Thanks to everyone for their replies. I will pop the hood tomorrow morning (raining here today), check the fuel shutdown solenoid (FSS), as well as swap out the FSS relay with another. Will update tomorrow. Thanks again! Randall, Oxford, GA