Engine/Transmission (1994 - 1998) Help....I turn key off- but stays running

[djbobo]

Anyone ever have this happen and can steer me in the right direction?



What stops a 12 valve diesel anyway?



dj

 

[Joe G.]

The fuel solenoid is not letting go. The linkage at the bottom of the solenoid may be sticking. Or your starter may be stuck. Or your fuel solenoid relay may be stuck. You had better fix this ASAP. If it's not the linkage it may ruin some expensive parts in a hurry.

 

[SRadke]

Definitely the fuel shut off selenoid. It is mounted on the side of the injector pump near the back. About the size of a film canister (maybe a little bigger) it is mounted vertically with a plunger rod out he bottom that moves a fuel shut off lever when you start to crank the engine or turn off the key. This may be an electrical problem or a bad selenoid.



-Scott

 

[Josparkz]

Fuel cutoff solenoid.

Look for a new one on e-bay, good deals can be found.

It can be manually operated (Turn on key, push solenoid rod, turn off key, pull rod{may have push/pull reversed})

 

[Joe G.]

Do some trouble shooting first. It most probably is NOT the fuel solenoid. That is one part that is often replaced when it is not broke. If you delay in getting this problem fixed you may destroy the fuel solenoid which is pretty expensive. If the problem is caused by starter contacts that is cheap and easy to fix. If the problem is the fuel solenoid relay that is also cheap and easy to fix. If the problem is sticking fuel solenoid linkage then all that is required is cleaning. A shot of brake cleaner and some air will probably do it. Of course, if the linkage is sticking and you replace the fuel solenoid then the process of doing that will free up the linkage making you think that you replaced a bad fuel solenoid.

 

[DDunse]

I had this happen to me once and it turned out to be the little hair pin looking clip that holds the linkage to the fuel shutoff solenoid. The little clip had some how spun around and just barely caught on some other linkage and that held it open. I reached in and with one finger just flipped it back where it belonged and presto... it shut right off and has not happened since.

 

[DCTECH]

I have also found the linkage will rust up on the pivot point of the shut off solenoid linkage and not move freely.

 

[djbobo]

Thanks everyone



I'm still out of town but will check things out this week-end. The truck is not currently driven so I have time to play with it.



From what you've been saying the solinoid is fairly close to the fuel filter. I did change the fuel filter just before I parked it. Do any of you suppose I bumped something loose hmmmm I'll check it this week-end.



JoeG -- I'm still wondering how the starter contacts are related to the fuel solinoid? It's not sticking. It starts like normal but when I turn the key to the off position the only thing that happens is the gauges turn off.



I'll get it



thanx again



dj

 

[Josparkz]

Let's see if I can get this right. The solenoid has 2 windings. It has a pull-in and a holding coil. The pull-in is paralled to the starter contacts, . Closes on key start. Contacts in starter arc together, leaving pull-in coil energized, and possibly starter engaged. Hard to hear w/engine running. Smokes starter, plus solenoid, they say.

The holding coil is energized by key/run position. This gives you your manual overide of the linkage option.

Alledgedley starter contacts last only 100K miles. Could be less if you're using non-filtered electrons. I changed mine after that , they were okay. About $30 in parts for them. Easy job.

This is the most common scenario with that sympton.

Relays and solenoids also have been known to fail.

Apparently Cummins has changed the design of the replacement solenoid, needs bracket mods and tweaking or somesuch.

E-bay is a good place to look for those n. i. b. old style solenoids.

There are a person or two on this board selling contact sets for the starter. There is also someone on e-bay sells full rebuild kits for the starter, w/contacts,bearings, and I think brushes, for not a whole bunch more.

Have fun

P. S. Oh yeah. It is a fuel cutoff solenoid, right at the end of the P-Pump. It shuts off the fuel supply to the pump, thus the engine, and vice versa.

 

[Peterbilt379CJ]

Look man, real easy fix. unplug the fuel solenoid, unbolt it from its mount and clean up the linkage. The linkage is what rusts so bad that it binds. you can hit it with spray lube but the problem will come back.



take apart and clean linkage really good and apply never seize to all moving parts. Never will you have a problem with this again.



Total time for job------ 45 minutes.





DRIVE PROUD... ... ... ... ... . DRIVE LOUD

 

[KB0OU]

Fuel Selinoid

I had problems with mine, sprayed it down with wd-40, no problem.

 

[J Shocik]

I would try the easy fix first, which IMO is the fuel soelnoid sticking. It happened to my truck, and the fix was to spray it down with WD-40, along with the rest of the throttle linkage. The problem came back once, so I did it again with no problems since. The soelnoid is to the right of the master cylinder on the engine. Hope this helps.

 

[Grayhackle]

Ok, I have been following this thread with interest. BUT noone answered the question of "how do you get the thing shut down if the key doesn't do it? Probably a dumb question, but inquiring minds need to know!

 

[DCTECH]

To manually shut off engine the lever on the side of the p7100 injection pump has to be pushed down

 

[SRadke]

DC tech is right on but keep in mind this is only for second gen 12 valves. Your 03 is a whole diffrent ballgame.



-Scott

 

[QRTRHRS]

djbobo, I did not catch the miles on your 12V? My starter contacts stuck. By the time I had the hood up, my selenoid was up in smoke (almost instantly). I could not be without the truck so the dealer got 400 bucks for the selenoid. Of course I still had to replace the contacts as well. IMHO, if you have a 12V with ~100k, replace the contacts. Just as important as the KDP.

 

[mainer]

DJBobo - Go to my thread "Hard starting '96" and check out Holeshot's reply that has a diagram showing the Fuel starter solenoid. It was a big help for me, and got me through my problem. Good luck

 

[djbobo]

Thank you everybody , the problem has been found



mainer-- I did read all of you post. Interesting reading on the PTO cable & replacing the whole assembly as a option.



QRTRHRS-- about 197k on the truck in question. So it's on borrowed time with some of these issues -KDP's are taken care of thanks to this site- Now LB's cantacts seam to be needed for the short list.



DCtech- Thanks on info on how to turn it off maneully- now I can shut it down instead of just stalling it out.



You to JoeSprks- I did follow most of your explaination (believe it or not). -- So intriged I just bought my own service manuel. OMG 80 bucks later.



The problem I have is in the solinoid. The pluger is no longer in it's socket. It fell out & is just hanging there. Don't know if it can be repaired.



We'll see



dj

 

[LarryB]

DJ

If the solenoid is slightly out of adjustment and the boot is deteriorated the plunger can fall out. You should be able to adjust it so it will stay in even without a boot. The original boot has a patented design that holds the plunger in. I have replacement boots on my site or you can use a piece of bicycle inner tube and make your own. I doubt that any damage has occurred to the solenoid.

Larry

 

[woody]

This is very interesting however my problem is slightly different. when i turn the key on and then to start it turns the engine over just fine but will not engage the fuewl selonoid, I can get under the hood with the key on and manually lift the pin in the selonoid and it will stay up and then I can start the engine and it will stay running until I turn the key off and it kills it right now. I can run a jumper to the selonoid and it will pull it right up and hold it but it will not do it from the ign switch. Replaced the relay that Dodge told me to, rather expensive) but it did not make any differance. Was wondering what the contacts in the started do, wonder if that could be my problem. Any help would be greatly appreciated.