Hi all, I have a 1996 12v diesel, I'm fairly new to diesels. I was driveing it and it felt like i was running out of fuel. So far ive checked the solenoid, replaced the fuel filter and fuel lift pump. From what i understand, there is only one piece of electronics and that is the solenoid. Is there any other electronics that might keep it from running, or any other ideas what could keep it from running. It was running fine and just quit. Any help will be greatly appreciated. Thanks harold..

 

Sounds like you are just throwing parts at it.

Do you get fuel at the fuel filter when you use the thump primer on the lift pump.
I ask as it am thinking you might be dealing with a fuel delivery problem. Think old fuel lines, loose clamps, ETC so you might be sucking air rather than fuel.

I also have to ask how full is the fuel tank?...

 

Sounds right, I've been throwing mony at it.

Is it leaking between the tank and filter. I tryed pumping the pump on the lift pump and it never got stiff like its not working. The tank has about 1/4 tank, maybe alittle less. It filled the filter, but I'm not sure what that means. Thanks harold

 

Maybe less than a 1/4 tank and it is acting like it is running out of fuel you say?...
The first thing to do is fill up the tank. The see if you can get fuel up to the fuel bleeder on the fuel filter.

If you are not getting fuel the truck will not run well...period.
Start with the cheap and easy in a case like this.

 

Do you mean the water drain on the filter or is there another bleeder on the filter. I got fuel out of the water drain, i don't know if there is a minimum pressure. I've been told to disconnect a line on the turbo somewhere. The truck has been leaking for some time, but but i haven't lost much engine oil? Thanks for your help, Harold

 

There is a small 10 MM bolt on the out going fuel line that can be cracked to bleed air out of the fuel system from the tank to the filter.

Draining fuel from the BOTTOM of the fuel filter using the water drain only shows you that you are draining some of the fuel you filled it with...

Watch a video or read a thread of "bleeding the fuel system on a 12V Cummins" or the like for more pointers, as I can not wrote up a full detailed write up on this right now.

What is the logic of disconnecting a "line" from the turbo? which line?

The engine has been leaking WHAT for a long time? Fuel? Engine oil? Power steering fluid? Anti freeze?

 

Did the truck lose performance, or shut off completely? Does it restart easily? I'm not clear on that from your initial post.

No matter what may be leaking, you don't want to disconnect a line on the turbo. The braided steel line is the oil supply - you don't want to disconnect that, or the oil drain line either!

What did you do to check the fuel shutoff solenoid (aka FSS)? Did you verify it is lifting fully and holding? The arm that the FSS attaches to is attached to a shaft on the injection pump (IP). There is supposed to be a woodruff key in that shaft/arm combo - verify that the key is there, and that the shaft moves with the arm and the arm isn't slipping on the shaft.

As Oliver mentioned - if there are any cracks in the fuel-supply line from tank to pre-filter to lift pump, you will get air in the system and have problems. These fuel lines are known to crack in their old age. It is also possible to have a crack/opening in the fuel-pickup tube inside the tank. If your problem goes away with a full tank of fuel, then reappears consistently when you get down to a certain level, consider that possibility. Note that issues like this often rear their heads when trying to start the truck, resulting in long cranking periods or a no-start situation.