Ok so I'm confused again. I went out and killed it again to check if the fuel finter is being sucked dry and its about half full. An inch up from the heating disk. When it seems to be loosing fuel because I can hear the injectors fire sounds like when you do a buzz test so I'm pretty sure that eliminates the hpop. When it dies I can crank it for about a minute and it will start and run on a few cilanders and then it catches. I can only think it is getting air in the fuel. This time I pushes the schrater when it was off I got some air out

 

Have you tried switching tanks? It isn't uncommon for the fuel pickup tube in the tank to get a crack in it and suck fuel when the level in the tank gets down below where the crack is.

Switch tanks or fill up the tank you are using and see if that corrects the issue.

 

I put a new tank in a few months back and the whole sending unit looked new or I would of replaced that too. It does it even on a full tank. Ill try the front tank but it seems to stop supplying fuel.

 

Is there a chance that one of the clamps on the tank didn't get tight? It sounds like you have air in the fuel. The way the fuel system works, the fuel pump PULLS fuel from the tank, so any leaks in the lines tend to suck air in and aerate the fuel. It is either that or the fuel pump is going south on you.

The other thing that may be an issue is the 6 way valve that switches your tanks. Especially if the switch doesn't seem to be switching between tanks properly, you may have an issue there.

 

Ill put fuel in the front tank today, the valve works I heard it switch. I did notice one of the stainless braided lines that goes around the powersteering gear box is rubbed threw the braids and I will cheak that out. Its one is the blue rubber on it( ones blue ones gray) I think blue will be suction and gray would be return?

 

I would have to look at the lines on my truck, but I would think (perhaps in error) that if the line were rubbed through you would see some signs of a leak there after you turned the truck off. It should at least be damp, but I would definitely give that area a second (or third) look.

 

The line doesn't seem to leak I cleaned it with some either and I will watch it. I'm getting more convinced its the lift pump.

 

Have you checked the fuel pressure when it is running? At idle you should be seeing around 55-65 PSI ideally. There is a Schraeder valve on the side of the fuel pressure regulator (driver side of the filter bowl). It has a black plastic cap on it. Just use a cheap stick style tire gauge to check it but be careful as it may spray some fuel. If you're seeing lower than that pressure, you might be correct in suspecting the fuel pump.

 

Sounds like fuel to me too. I don't get the 2 years apart thing though ..

 

What are the other possibilities? The truck drives fine untill I'm on the highway. When it dies like I said I can still hear the injectors fireing and when I take the fuel filter out the fuel level is below the black tube in the center so I know its running out of fuel. The only thing I can think of now is the pump. I will check the pressure but it seems like the pump looses suction power at high rpm. The pump is 109 at napa but to take the intercooler tubes off and spend the time and money I just want to rule out the possibilities.

 

Fuel pick ups , collapsed fuel line , blocked vents , Sucking air (not usually at cruising speeds) .. Is it on either tank?

 

I have not tried the front tank it leaks and I havnt had the ambition to put the new one in but the rear is a new tank and the sending unit is like new and all the lines look good minus the one spot on the braided line. I can try the front tank but I have a feeling its going to be the same but I want to rule it out. The braided line I have anoter I will replace it with off my parts truck. Vents as in fuel cap vent?

 

Either the cap or tank. I don't actually know if our trucks vent through the cap ...Plugged vents can collapse a line ...

 

Ok. The tanks do have a vent on top I do rember I blew it out to make sure it was working. When I open the cap I don't have and vaccume in the tank. My guages are at work but I pushed the schrater valve and it doesn't have much pressure. I have done it before and this doesn't squirt like it should

 

Sounds like the pump to me. FWIW, the only place that manufactures that pump is Carter, so regardless of where you buy the pump or what name it has on it, they are all the same. Shop around and find the best deal you can, because they're all made on the same line.

You should also plan to but a couple sections of diesel rated (SAE 30R9) rubber fuel line and some "fuel injection style" hose clamps. You'll need some 5/16" and some 3/8" (only a few inches of each but I would just buy a foot of each so you don't come up short). Replace the fuel hoses that connect the pump to the fuel bowl and lines while you're at it so you don't get it all back together just to find it pissing away valuable diesel from a leaking line.