Ok, ran into a problem tonight, I left my truck in a steep driveway overnight and now the truck will not start or run. I started the truck on the hill and it idled and ran fine for about 20 sec., I gave it some fuel to keep the idle at about 1k then it started clugging and choking and died. Now truck will not start or idle on its own. I can crank the motor but it wont start untill I give it about 3/4 pedals worth of fuel and hold it there, and it starts but tons of gray smoke comes out and it just cluggs and chokes the motor and wont run. There is about a 1/2 tank of fuel but it all would have been at the back of the tank on the hill. Did air get in the line, or what would cause this? The temp is about 40 deg.

 

maybe change the fuel filter and prime the fuel system there is a plunger on the lift pump just push the heck out of it to prime ur system usually it is a black cover on it but if the cover is gone then it looks like 3/4 inch pvc sticking out ur block to maybe try and bleed the lines of air faster loosen the number 1 dv line on the pump just a little dont take it completley off my truck puts out grey smoke but only when it is cold and has just been started when it warms up it goes away
good luck

 

We are in the same boat!!! My truck is acting up and doing the same thing when I park in my drive way which is sloped. Two days ago I had 3/4 a tank and started great, but now at 1/2 the past two days it is doing the exact same as yours. It has been doing this on and off for quite a while now. This is driving me nuts, I hate smoking out the neighborhood with white/grey smoke for 5 minutes until the truck starts

 

It's the return line letting air into the system.

 

I am going to go ahead and replace the return line and hope that fixes it.might do it today if I can find it at a Cummins house around here. Is there any way to check to make sure that is the problem, and not another line? This morning was rediculus the time it took to start and smoking out the whole neighborhood for a few minutes while I layed my foot into her to keep her from stalling again, while it warmed up. As much as I like smoke it might have been alittle excessive this morning

I just want to fix this

 

Not the return rail at the injectors, the hose from the engine back to the tank is what is leaking.

 

Well, we replaced the filter and bled out the lines and now it seems to be working for the moment. Thanks for the ideas.

 

If the problem comes back , check the fuel pressure , I had the same issue , tank down to about a 1/4 , on a hill .
Both the lift & overflow valve was getting tired .

 

last year or so i had problems starting if i let it set for a few days it would take forever to crank then it would idel funny for a few minutes and everyone said it was my return also and after checking the price at the local dodge house i decided to actually find out what was leaking turned out it was my lp it was leaking from the "weep" holes we replaced it and the fuel heater bowl cause the wires for it was burnt bled the lines and changed the filter and now everything was ok i didnt even think about this the other day when i posted u might wanna check around the lp when u get it running and see if it is leaking mine got so bad that eventually it only had to set for 6-8 hrs and it took 5min to crank up

 

Mine was slightly worse this morning and started leaking diesel while running. I decided to really dig into it. Turns out it was not the return line at all, a bolt/washer was slightly loose on the fuel drain manifold on the rear injector. I tightened it back up and she ran like a champ with no more leak. I am almost 100% positive it will start great in the morning. This would solve the mystery as to why it ran great for a week after having the head gasket replaced then went back to hard starts on Sunday.

 

The most common cause of incline parking related refusal to start is a deteriorating suction line in the tank. When the tank is full enough to keep the suction line cracks under fuel, no problem. But, once the cracks are exposed they lose their prime and fill with air.

There are several excellent replacement suction hose kits that pretty much solve the problem forever, and I would expect this site's store or sponsors have at least one.

If you allow the problem to continue and simply reprime the system on the level, it will eventually knock out your overflow valve from allowing it to sit dry.