Hey guys, had some engine problems this morning, need to fix her up tonight, so if anyone is around to chime in before I tackle this I would appreciate some advice. (Truck is a ’93 Cummins 4x4)

Was driving to work this morning, -15 degrees C. Warmed up truck for 10 minutes and off to work. Drove for 20 minutes without issue. My engine reached full operating temperature. I had to pick up a buddy to head to work, so I pulled up at his house. I literally rolled to a stop in front of his driveway because my engine shut off second before I got there…. Dumb luck.

I had little time to get to work, so I didn’t do much to get it going, but the engine was hot, it cranked over fast, but would not start. I tried applying foot to pedal and no dice. I ran a jumper from my battery down to +ve wire on my ELECTRIC lift pump. It turned on, so seems good. Its not very old. No obvious issues anywhere else.

My plan once I get it into my shop this afternoon is to perform a test for power at the fuel shutoff solenoid. I want to make sure that I am getting 12 volts at the solenoid, and that there is no dead short within the solenoid itself. I may have to pull it out to inspect it. I have had no smoke or sighs of split fuel lines or plugged fuel filter. Lots of power and runs great. This happened totally out of the blue.
One question: is there a relay to run the fuel solenoid? Or is it direct?

Any thought on what to check would be great. I have never done work on a diesel engine before, because I have never had to. Other than bleeding fuel system on the tractors. I will be sure to check for fuel at the injectors if all looks good at the solenoid.
Any input at all would be awesome, as I don’t want to miss something cheap or obvious.
I have half a tank of fuel, so Im sure that its not empty. With the hot engine, it was cranking over faster than my gas truck on a summer day, so that isn’t causing it not to start either.

Thanks for any ideas- Ill be sleeping on buddies couch if I cant get the old girl going! So fingers crossed!

 

the solemoid is a plunger that is activated by the voltage, if there is no voltage, then the plunger does not get out of the way to let the fuel through, that is the best place to start.

 

Alright, so here is the update.
Got the truck in the garage after work, plugged in battery charger and block heater and left it for a few.
This was my trial and error process:

1) Removed +ve lead from fuel shutoff solenoid. Turned on key. Taped +ve terminal with hot wire and hear clicking of solenoid. I did this a number of time and determined it was moving.
2) I then cracked #1 injector and tried to crank the engine to look for fuel up at the injector… at this time, the engine would not crank. Long story short, I found that my starter circuit relay was burnt, so I had to take it apart and clean up all the contacts in there. Once this was done, the engine was able to crank without issue.
3) Once I got the engine cranking, I again cracked the #1 injector and spun the engine. I saw fuel . I then continued to bleed out the injectors in order. By injector 3 I had smoke, 4 I had a kick, and 5 she was running strong.
4) I drove the truck to work this morning (30 minutes) and had no problem. Everything functioned perfectly.

So, now I am paranoid that she is going to quit on me at a much worse time or location. The fact that I didn’t find a smoking gun is concerning, as nothing is really fixed. I don’t think the starter relay has anything to do with the fuel system. Is there some sort of feature on the engine that cuts fuel in the event of a stall? I am still thinking I might have accidently locked up the brakes and forced the engine to stall when I slammed them on too quickly. (I was sliding on snow)
Not sure if this could have any effect.

Please, any thoughts or ideas as to what to look at or check, please let me know.

Thanks.

 

is your shut down solenoid wire connected to the started relay in any way shape or form? if it is and you opened the circuit off goes the engine. i think you found your smoking gun.

 

Well I knew that it wasn’t solved, no smoking gun is never a good sign.
Anyways, after my shift ended, I tried to start the truck and she wouldn’t even kick. I got my buddy to crank it and I again bled out the injectors. She started right up.
I drove it for about 5 minutes, and it felt perfect.
Then it bogged down hard. I pulled over and had to keep giving gas to keep it running. There was a ton of smoke. I let off the gas and it died.
I then again bled the injectors, she started, ran for 30 seconds, then stuttering and smoke, and died again.

So clearly I have a more serious issue. I had to tow it home, and left it on the driveway, tempted to start fire to it for the insurance money… decided to sleep on it.
My one thought is that a clogged fuel filter may be causing the injector pump to suck air at a joint… I will replace filter. Other than that I was planning on inspecting fuel lines, checking joints, etc.
Im hoping its something as simple as this. Whatever is causing air ingress seems to be happening when the engine is off or on, which makes me think the fuel filter isn’t the cause. It seems air is getting in even when it is just sitting for a period of time.

Perhaps the return line check valve is allowing air back from the tank? That is something to check…

Please, any ideas to aid my process would be much appreciated. This is my first time working on a diesel engine, so Im going from logic here…

 

That is consistent to a failing lift pump. A mechanical lift pump may fail intermittently at first until a complete failure occures. It is a simple 20 minute fix that should be done about every 250,000 miles.

 

Here is my happy update!
I took the weekend to work on the truck.
First thing I did was pull the fuel filter and replace. Filter was clean. No smoking gun. I was then going to remove all fuel lines and start replacing everything on the low pressure side. (ortegaej, note that I have an electric lift pump).
Anyways, I went to pull the line out of the discharge side of the pump, and it turned a little too easily... I then unscrewed it with my fingers. I then unscrewed the intake side, again with my fingers.
This looks to me like a smoking gun. I torqued down the fittings, and bled the air at the fuel filter. I then got the ol' wifey to crank the engine while I bled the injectors, and within minutes I had the old girl purring away. (the truck that is).
I have driven a few miles without issue, and started perfectly this morning. SO I am hoping that that is all it will need for the next half million KM's! Ill know if I make it to work on monday.

Thanks to all who provided input. Hope the problem has been solved!