With your update, I suspect that you have an air leak but don't rule out the solenoid. The post above is correct that the supply fuel line is 3/8" ID and the return is 5/16" ID. I would suggest running the rubber right from the top of the tank to the engine and back. The steel lines on the frame can rust out and it is just easier to put in all rubber. I don't remember the exact length but I think it was a little over 15' of each size for my truck. The tank ends of the line is hard to get to and most people either drop out the tank or remove the bed of the truck for easy access. I did mine by jamming my body up between the outside of the frame rail and the bed and it was easy enough to do. There is also one more very short line that is larger in diameter between the fuel heater and lift pump that is probably worth replacing.

If you are breaking into your fuel system, you will have to be ready to prime it again. The easiest way is to use an air hose with a towel wrapped around it sticking into the filler neck of the tank to provide a few psi of pressure to push the fuel through the lines and out the bleeder screw. If you don't have air, pumping the primer bulb on the LP a few hundred times will prime it and give you a blister on your thumb.

Before you go nuts working on an air leak, it would be worth checking the shutdown solenoid in case you actually have a real simple problem. To check this have someone else try to start the truck while holding your finger on the plunger of the shutdown solenoid(located on the back of the IP, it is vertically mounted). This should pull up and stay up while they are trying to start it. If it isn't, there are a couple of possible causes. I don't think that this is your problem but since it only takes 10 seconds to check, it is worth it before you dive into your fuel system in the cold.

 

X2 on that, especially since you've got a lift to work on

 

hi there i had a simular problem had to krank it for about 2-3 mins with pedal down ,,, there are 2 fuel lines behind the fuel filter , if they have a pin hole there is your problem , at the age of the truck it is no waste on doing them lines , i think thats your problem ,, good luck and let us no if you fix her up

 

So I just went out to move the truck into the shop.

It's -10 celcius and it wouldn't go. I got and and primed the pump using the plunger.

After about 50 pumps I could hear and hissing sound coming form the injector pump area somwhere. Sounded like pressure of some sort bleeding off. The more I pumped the stronger the sound.

After that the truck started.

Once on the hoist I took a look under truck. For sure I will need a new sending unit. Looks pretty rotton on top of tack and the maybe a little wet.
Would I be better to replace all the steel lines with factory steel as well while I am there?

What type of tool does it take to remove the special fitting on the fuel lines approaching engine block?

 

It sounds to me like you have proved it is an air leak since priming it did the trick.

The factory steel lines along the frame rail should be dealt with while you are at it. I would suggest doing away with them completely. Not only is it easier, you won't need any special tools to connect or disconnect anything, it will all be hose barbs, hose clamps, and rubber hose.

Good luck getting it done.

 

make sure you use diesel rated fuel line. The stuff at napa and auto zone is gasoline rated not diesel. i bought mine at West Marine.

 

I thought I posted this note already but it must ahve been lost in cyberspace.

I put it on the hoist last night to have a look. IN order to get it going I had to prime the pump manually. After about 50 pumps or so I could hear some kind of hissing sound. Like pressure or air coming off somewhere around the injector pump area. Couldn't identify exactly where.

After priming it started right up. What does this mean?

Also it looks like the sending unit is rotted right off. So I will replace that too.

Should I just put all factory steel lines on or should I do runner all the way to the front?

No doubt the rubber is less money.

Thanks for all you help guys.

 

Alright ignore that last one. I forgot to refresh my screen.

 

Many are running the marine hoses all the way .

 

So I took the tank down and remove the sending unit. Easy with a hoist. Just set the tank on tranny jack and lift the hoist. While I was inspecting I also noticed that the dealer hadn't tightened the lift pump bolts or the bolts on the intake manifold!!

The fuel line connections were very bad and broke off while dropping the tank. If this isn't the problem then it still needed to be done. The entire sending unit assembly was $200.00 canadian which seemed not to bad since the filler neck is $260.00 canadian.

I am off to buy some 5/16 line and 3/8 line from napa now.

I figure one runs right to the lift pump but I havn't looked where the return line comes from.

I noticed that some of the lines are braided steel. Any worries with replacing those with just rubber.

 

DIESEL rated fuel lines.

West Marine has some really thick walled rated line.

 

I got diesel rated fuel line at my local Napa, just had to ask for it, 89 cents a foot.

I ran new steel lines from the front of the tank up to where the factory disconnects were, rubber from the tank to the front of the tank and rubber from the start of the floorboards where the old factory disconnects were up to the engine. Was pretty simple once I got the fuel filter out of the way.

Don't even bother with pricing Dodge lines, they are stupid, and if you want to disconnect the lines, you use a standard 5/16 and 3/8" fuel line disconnect tool, though you don't really have to if you are replacing the whole line.

 

You can get reconditioned sending units from the dealer, If they give you grief just come back here to get the part #.

half price.

 

Not at all. Run the hose through some plastic electrical loom if you want to protect it further.
I prefer to use USCG rated fire resistant hose. It's twice the thickness of anything Napa sells and should easily last the life of the truck.

 

the previous owner of my truck lived in maryland with some cold temps.
He had the same problem as you.
During the troubleshoot he replaced the grid heater...

Turns out it was the return fuel line.