I posted a query a couple of weeks ago about a '95 that was losing prime overnight. Ran fine after it was started, but might take a minute to start. A few of the suggested fixes were the lift pump going out, fuel filter change, and fuel line sucking air. I can't see any leaks any where. After I put a new fuel filter on yesterday, it attempted to start then acted like it was out of fuel and died. I bled the system using the bleeder screw on top of the fuel filter. No change. I loosened the lines to the injectors and fuel is not getting that far. I loosened the fuel line coming in to the injector pump and I get fuel if I use the hand pump on the lift pump, but not if I turn the motor. I removed the new filter and it is full of fuel. Not sure where to go from here. Lift pump gone? If it's gone, would the manual side still work? I've notice the fuel shutdown solenoid is hot! Is that normal even when the motor will not start? The solenoid is moving, any chance it could be bad and still move correctly? I'm pullin' my hair out on this one folks.... Closest Dodge dealer with a diesel tech is about 30 miles away. Anybody in the neighborhood? :-)

 

Where are you?

 

DId u try manually priming it?

Tx

 

I have tried the manual prime. No help. I'm in Royse City, Texas.

 

FYI, in most cases with leaking supply or return lines, you WONT see leaking fuel. The fuel lines degrade and develop very tiny holes that let air into the system.

If you havent replaced them - its time - whether this is the problem or not.

www.fostertruck.com has some very good replacement line.

 

If ur not getting fuel to the injectors,

Maybe ur lift pump is bad. It could be the lines once again, and i could be wrong, in this case i hope that I am.. But, it strikes me as weird that u arent getting fuel, what is the mileage on this truck? any ticking noise from the lift pump? The P7100 rarely fails, so i doubt its that... lift pump failiures are uncommon as well, so it would be my guess, if it aint the lines, then id look into that..

Tx

 

If the fuel filter filled, the lift pump is working.
Often, you have to hold the pedal to the metal to get the pump primed and delivering fuel to the injectors.

The solenoid draws a lot of current if the plunger doesn't fully lift.
Test it by turning the key on and then get under and lift it by hand. It should hold in place at fuel on position (full up).

Changed the overflow valve?

 

If you have been trying to start it repeatedly it's likely the battery charge is way down. Even though it turns over it won't start unless the engine is spinning fast enough.
Put it on a charger.

 

Manually pull the shut down solenoid all the way up when cranking.

Crank at WOT, untill it fires.

Unplug the grid heaters, shoot it with some ether to get the RPM up higher.

Give those a try, and report back.


Merrick

 

Perhaps im mistaken here

Isnt the fuel filter supposed to have diesel in it when you go ahead and put it back on truck? Hence my guess for lift pump is dead. Ive never ever had trouble starting my ram after a fuel filter change. I just give it a lil pedal when i bop the key and it goes. Ive never needed ether either, nor messed with grid heaters. Perhaps ive been lucky.

Try Merricks idea, if that dont work?

ID say you might have wayy too much air in system and bleed it out somehow..

Tx

 

I've always used the manual levver on the lift pump to fill the filter after I've put it on the truck. Never have had an issue. Would air in the line cause it to stop flowing fuel from the filter to the injector pump?

 

No, air will flow to the injection pump, out the overflow valve and back to the tank. Problem is an airlock in the injection pump, only way to get the air out is to crack open at least three injectors lines and turn the engine over till bubble free fuel appears.

 

I've tried that already and I can't even get fuel to the injector pump without manually pumping the lift pump.

 

You should never prefill a fuel filter. Why put dirty fuel in the clean side of the filter?
The primer button is just for that purpose.

 

I agree you normally can't see a fuel line leak like this, what you have to do if you want to see the leak is pressurize the fuel tank. Don't go wild, just a couple psi.