Engine/Transmission (1994 - 1998) help somebody help

[JHaywood]

1994 3500,300,000 miles #6 plate

truck will not start,cranks over fine. fuel shut off replaced with manuel cable,its working fine. i figure it should be a fuel problem. what are simple checks i can make in driveway?thanks!

 

[Joe G.]

Read this:

http://dieselram.com/ubb/ultimatebb.php?ubb=get_topic;f=45;t=000007

 

[Howard Durand]

Was it fueling before you changed to the manual cable?

 

[JHaywood]

the kdp has been fixed,and yes it was fueling before. it started this morning,was moving boat around,put it in reverse,started to miss,mashed accelerator,rpm stsrted to rise then died. cranks over fine,sounds like always,no knocks,ect.

 

[JoshPeters]

Sounds like you definatly have a fuel issue. I'd check/change your fuel filter, and hit the primer button a couple hundered times. :-laf



Not to be a smart @$$, but are you out of fuel?



JP

 

[JHaywood]

not out of fuel. isnt there a fuel pump that delivers fuel fron the tank to the injection pump?if so how do i check to see if its working?

 

[Woodenhead]

Yeah there's a mechanical lift pump on the drivers side of the engine near the bottom. It runs off of a cam on the cam shaft. Follow the line from the filter and you'll find it. You can crack the filter loose a few turns and crank the engine over. If the lift pump is good you'll see fuel start spilling out. They're pretty reliable but with your mileage it is possible this is the problem. Did you notice symptoms of low fuel pressure before this such as hard starting or low power? Crack a few injector lines loose at the injectors and crank it over to see if you're getting any fuel.



Did you just fill the tank? If it was running fine up until now maybe you got a bad batch of fuel. Change the filter and try it again. Also, don't crank it for too long and end up cooking your starter.



Just a few suggestions, good luck and keep is posted.



Mike

 

[Joe G.]

Read the article at the link I posted above. It is NOT a good idea to mess with the fuel filter until you have some idea what is wrong. If you do that, then if you have an air leak you will have a very hard time priming the filter. That just adds more complication to the problem. The lift pump seldom fails. It's usually an air leak somewhere.

 

[JoshPeters]

My question is if he got a bad enough load of fuel to plug the fuel filter.



If he has an air leak that big to kill the engine and not cause a hard/no start condition before that... . something completely let go.



I also wonder if something in the governor assembly didn't fail. I had to replace an injection pump due to a dying condition. It would restart... ... most of the time... . at times it wouldn't others it would.



Here is how I start my diagnosis on fuel system issues on these trucks. This is just me, do as you would like. I have access to a fuel pressure tester, some people don't.



Shut down solonoid.

crack an injection line. Fuel or not.

change the fuel filter, fill it prior to installation. Inspect the contents of the old one. Possible critters or dirt.

Check the fuel heater screen. Same as above. (I have removed the fuel heater on my truck with no ill effects they tend to get air leaks)

check the overflow valve spring length.

check the fuel pressure.



if it passes everything above, you have an injection pump issue.



JP

 

[Joe G.]

I do it differently. First thing is to check fuel pressure after the fuel filter. If no gauge just loosen the bleed screw and see if there is plenty of fuel there. If that's ok then there is something wrong in the injection system or the fuel solenoid. If no pressure then crack the banjo fitting on the input to the fuel filter. If plenty of fuel there and none or very little after the filter then it's a plugged filter. If little or no fuel at the filter input then it's probably an air leak so I check all the stuff that could leak air. If all that is ok, then I take a close look at the lift pump.

 

[Howard Durand]

What prompted you to remove the shutdown solenoid and change over to the manual device? Are you sure it is opening the fuel valve?

Also, how does the fuel tank get air so it doesn't build up a vacuum?

 

[JHaywood]

auto shut off quit woeking for the third time. yes the maunel shutoff is working,checked it first. dont know about the tank vent. havent found anything yet. thanks!

 

[jhawkins]

I had the plastic water in fuel valve that is mounted to the bottom of the fuel filter fall out after which I could not restart.

 

[JHaywood]

not much time to do much to truck around here,building a new nitro harley motor after work, but did check fuel lines,didnt see any fuel leaks,removed fuel eilter,filled new one with fuel,left the new a little loose,cranked her over,no fuel ran pass filter. read to do this somewhere. so im thinking the lift pump has let go,or massive air leak somewhere. wife sayes were going to the lake today. so were going to the lake!! thanks everyone,will keep you up to date as i get things done.

 

[Matthug]

Fuel passes through the pre-filter screen and fuel heater first before going to the lift pump, check there for clogging since fuel is not making it's way to the fuel filter.

Here-

http://www.dodgeram.org/tech/dsl/filter/pre-filt_clean.htm

 

[Joe G.]

You can't see an air leak so the visible condition of the fuel lines does not mean anything. They can look great and still be leaking air like crazy. The fitting on top of the fuel heater/pre-filter could be leaking. It has as composition washer in it that can go bad. The fuel heater could be leaking air in the electrical connection. The curved hose between the pre-filter and the lift pump could be leaking air.



Remember, the lift pump cannot pump air so just because the lift pump is not working does NOT mean it's bad. You can check it out by removing the curved hose and replacing it with a hose you can put in a bucket of fuel. Any component before that can have an air leak and be killing the whole works.



An air leak is the most likely cause of a fuel supply system failure.

 

[JHaywood]

Thanks Everyone,not Working Today,removing The Lift Pump Today If Rain Stops.