2005 Dodge 5.9L Dsl Extended Cranking Before Start

[MAS1866]

Hey there all. New to using this forum so please bare with me.
I've got this 2005 5.9l dsl in the shop annd I have limited experience with them. It belongs to a friend or I might not have gotten into it.(that and I always like new stuff to learn about.)

It came in because of extended cranking before it will start. And there are enough of theese things around here(and I've had enough in) to know that when they are at operating temp. they barely need to crank one rpm b4 they fire.
How does a guy go about testing the fuel limiting valve(fuel pressuure relief) on these 5.9`s? I've done all of the fuel volume checks and everything checks out. I've checked and retorqued vall of the high pressure fuel lines and crossover tubes and there doeesn't seem to be anything wrong there. So i'm down to the fuel pressure relief or a set of injectors.

Thanks in advance for any help.

[steven kiser]

Is it only when the temp drops below a certain point or every time they go to start it? Are there any codes? when it finally starts is there a plume of black smoke from the tail pipe?

[Tim Martin]

One thing is to check fuel pressure from tank to engine. Also what is fuel rail pressure when engine is cranking?

[mopwrforme]

you are correct to ck. volumn not preasure on the low side fuel system. if its to spec. make sure you have + or -
500 psi on the high side youll find a set point for the high side in the data stream. if your lower on the high side
and its taking a little time to build up high side preasure you can ck. high side pump output its a volume ck. while crking. if it does pass the test then go to your injector return to the tank, there is a galley in the head which
returns unused fuel to the tank that will tell you if your injectors are leaking externally into the galley.also before you do anything ck. the oil level in the crank case,if its overfull, while running remove the oil fill cap,if the overspray from the leaking injector blows your hat off guess what you got too replace. good luck


welcome to the forum

[steven kiser]

I guess they figured it out. The other thing i experience in colder weather is if a battery is even borderline it will cause a slow crank, hard start. When my cummins fires up after the "wait" light shuts down it sounds like it's starting on the old 24v systems the big trucks had. If the fan blade wasn't on a clutch the force from the blade would pull the truck across the lot.

[MAS1866]

Sorry it took me so long to get back guys.
The problem persists even if the truck stays in the shop, although not nearly as long.

I have pulled the banjo bolt out of the back of the filter housing where the fuel line from the back of the head goes to the filter housing then goes off to the tank. There was a lot of fuel coming out when cranking. Is this the right prosedure for this test?

I have also changed out the fuel limiting valve because when I cracked the bolt on top and cranked the engine I has fuel bleeding through the FLV.
Also checked and retorqued the crossover tubes for the injectors.

[steven kiser]

I would look into the glo plugs or timer.

[mopwrforme]

you would ck. glow plugs if it had them. a 5.9 cumins has a heater grid in the intake which
super heats the air going into the intake and then heats the fuel via the filter houseing
for cold starts usually if the heater grid is bad it will start but have a rouf idle until it warms up

I guess if both the intake heater grid as well as the fuel heater went bad togeather you would have issues
personally make sure you use the proper fitting what you are doing with the correct fitting is blocking off
fuel comimg from the filter circut if im not mistaken.so you can get an acurate reading on the injector return
flow. its posted in mitchell under injector return flow test. fuel circut diag on these trucks is a bear and
can run you around in circles if not done by the book. first i would ck the high preasure fuel rail set point

if its + or - 500 psi on initaial crk. you dont have a fuel preasure issue. if it crks for say 5-6 sec. or more then reaches its set point and fires up yes go further with the fuel system tests. start with a low side volume ck.
the specs are posted in mitchell, if you have plenty of fuel volume into the filter next is there no more than 5psi

variation between the inlet and outlet of the fuel filter, if so change the filter and retest. next is the high preasure pump its also a volume test x amount of fuel after so long of crking. if the truck runs its usually ok. a bad valve in the high side pump wil cause a fluctuating idle it can divert fuel back to the filter but i have yet to see it. if the pump is that bad you will find it on the volume while crking test. youll get very little or none out of the pump.

if at this piont if all your tests have past. ck your injector return flow. all of these tests will need the proper fittings in the correct locations to get the proper result if you can go into on demand 5 punch in your yr,make,model click on tsb then go to the tsb by # the tsb # is 14-003-06 rev.a it gives you the step by step
for fuel system diag on this truck good luck