truck still won't start ---help !!!!

[bigjim]

1996 6.5 turbo k3500

i was driving along on the highway,truck started black smoking,then white smoking. engine rpm's started reving up by itself. (3000-3500 rpm's)
i pulled over and the truck was leaking fuel at the fuel filter housing. i replace housing and bled system. no air. truck cranks over but won't fire.
( i have good fuel pressure at injection pump,no fuel is coming out the injectors.)

i have fixed the fuel leaks and the truck still wont run.

thanks, jim

[More Power]

I would proceed as though the only problem was the leaking fuel filter housing.

On that assumption, your fuel injection system is likely airlocked.

1- Make sure the fuel filter is properly bled and no air is present in the fuel filter assy.

2- Make sure the electric fuel lift pump is generating fuel pressure when first turning the ign key to the run position (for 1996+ systems).

3- Crack open at least one fuel injector line fitting on each side of the engine.

4- Crank the engine in 20 second intervals, with a 2-3 minute starter cooldown period between cranking sessions. Look for fuel at one or both loosened injector fittings within 2-3 cranking sessions.

5- If no fuel, wrap your hand around the shut-off solenoid, and have someone cycle the ignition switch between off and run (do not crank). You should feel/hear the solenoid clunk. If not, you need to find out why before cranking the engine again.

6- In severe airlock situations, I've dribbled about a 1/4 to 1/2 teaspoon of diesel fuel through the front center top intake plenum bolt hole (there are six bolts holding the top half of the plenum onto the primary intake manifold - remove just the front/center bolt.)

7- The engine should stumble and miss with the raw fuel, but it'll crank faster with the added help of the fuel. This should speed expelling the air.

8- Once it begins to stumble, tighten the two previously loosened injector fuel line fittings.

9- Repeat step 7 and crank again. Eventually it'll begin running normally.

Jim

[bigjim]

hey thanks for the help

1) i double check and bled fuel filter and drain at the front of engine-no air.
(psi will keep pumping at the filter,it slows down at the drain tee.) but no air.

2) yes it does-everytime (not sure how much,but it pump a good bit.)

3) i cracked both front injectors and zero fuel

4) no fuel at either line

5) yes ,the fuel solinoid it clicking

6) done that and still wont start

i had a spare pump drive that i installed and this made zero differance.

i still think that the problem is from the fuel leak issue. but starting to think PUMP ?

any help would be appreciated.

jim

[bigjim]

ok,i went out and tried everything for the 8-9 time and i got alittle progress.

when cranking i put the fuel intake and the engine fired,but didn't stay running.

my battery is weak,i'm charging now. i hope that this thing is just air locked.
(( no fuel came out the injectors.))

Thanks for the HELP..

jim

[Hubert]

6- In severe airlock situations, I've dribbled about a 1/4 to 1/2 teaspoon of diesel fuel through the front center top intake plenum bolt hole (there are six bolts holding the top half of the plenum onto the primary intake manifold - remove just the front/center bolt.)


You say you did this? Did it cough or try to start at all stumble etc? IF not try it again add a double dose of cetane improver additive to the diesel fuel you spoonful into intake.

Is it cranking fast or cranking slow?

[Hubert]

Dang, I am a slow typer. Actually wrote some more stuff then thought better of it and while I was finishing post you answered my questions.

I'd charge up the batteries good and repeat it a few more times. Keep us posted.

[bigjim]

6- In severe airlock situations, I've dribbled about a 1/4 to 1/2 teaspoon of diesel fuel through the front center top intake plenum bolt hole (there are six bolts holding the top half of the plenum onto the primary intake manifold - remove just the front/center bolt.)

i did # 6 and it fired over,but didn't start.

it's cranking over slow,but battery is also low.

thanks , jim

[charliepeterson]

When the engine starts to runaway by itself (3000-3500 rpm's) the injection pump has failed. Try putting a scan tool on and your looking for injection closer times being too short or any codes relating to this.
By running away I mean engine rpm goes up with NO additional pedal movement. You might be able to duplicate this in neutral or park. Bring the rpm's up to about 1400-1600 and don't move your foot. The engine should stay right at this rpm and not climb up by itself.

[DmaxMaverick]

An airlocked fuel system will do that, as well. The air will delay injector pop (retarded timing), but should clear once the air is expelled. If you have air, you should not be able to hold a steady RPM.

I suggest having a closer look at the lift pump and related components. If it is sucking air while running, between the lift pump and I/P, the lift pump isn't working. An air leak that doesn't leak fuel under pressure will likely go unnoticed. If it is still sucking air, and the lift pump is working like it should, then you have a leak between the pump and tank pick-up, which can be the fuel line, or the sending/pick-up unit. Also, check that the fuel cap is venting properly. Vacuum that builds in the tank will create, or exaggerate small leaks.