Fuel problems.

[Josmuck]

Good Morning,

First off I just want to say thanks for any help.

My truck is

1994 K2500 HD 6,5TD. No clue as to how many miles. The truck is a pieced together truck . If it
Has 50 original parts on it that is a lot…

So this is what happened. We have been driving it in and out of the garage to work on other trucks.
Starts great in both cold and warm environment.

Last week we drove it out and it stalled! Ok started it back up and moved it 20ft and stalled again!
Looks like the tank was empty, I guess the gas gauge is not quite right. Got some Diesel and after Taking the air out of the lines and filter it starts back up. Now, last night I want to drive it back out and nothing, absolutely nothing. Will not start. Again bleed the lines and filter again with no help.

Could the IP have gotten damaged or sucked up so much crud from the empty tank? We bridged the
Diesel pump so it stayed on and still nothing.

Thanks for any help.

Brian

[Dvldog8793]

Howdy

If there is no smoke when cranking then you have a fuel supply issue.
If you are getting fuel to the cylinders and cranking over good and fast with a good glow circuit, it should fire. UNLESS you have some catastrophic failure, but it doesn't sound like you do.
If you suspect air in the system, do a search on this forum and you will come up with tons of information. Search window is in the right hand corner of the forum page, kinda small but it s there.
There is a step-by-step process for clearing out a fuel system.
Good luck!

[Josmuck]

Hi dvldog,

Thanks for the info. Nothing is coming out of the exhaust and seeing how it
has been removed up to the cat I would think I could see something. I have checked the search but might of been looking for the wrong title.



Cya

[Dvldog8793]

Howdy
Try this:
Open the bleed valve on the filter, bridge your lift pump again and see if you have fuel to the filter.
If your supply line is SUCKING air from before the lift pump you may not see a wet line.
If you have line problem AFTER the lift pump it will be wet and leaking.
If you have fuel at the filter, close it up. Move on to the next component,
Pump/injectors- crack an injector and see if you have fuel to the injector, if NOT then you have an air locked pump, fuel solenoid failure or possibly a PMD failure.....Is this a DB2 or a DS4?
Verify that the fuel shut off solenoid is working properly.

[Josmuck]

I think that is the next thing I will try. I am just worried that the IP is dead! I think that is the most expensive part on the whole truck!

I keep reading that you can also take out the glow plugs! Does that really help?

Cya

[Dvldog8793]

You can take out A glow plug and then turn it over to see if there is a fuel mist coming out of the hole.
This will let you know if the injector on that hole is working.

[Josmuck]

Well Carp

Took Out the solenoid and removed the Pin, Cracked Open the injectors and NADA! Still not Running. Diesel is getting to the IP But nothing After. If the ip is vapor locked what can i do there?

Sorry for all the cap mistakes i live in Germany and the stupid spell Check is on

Cya Brian

[JeepSJ]

Well Carp

Took Out the solenoid and removed the Pin, Cracked Open the injectors and NADA! Still not Running. Diesel is getting to the IP But nothing After. If the ip is vapor locked what can i do there?

Sorry for all the cap mistakes i live in Germany and the stupid spell Check is on

Cya Brian

Remove glow plugs. Crack open all injector lines (some people say you can do this with just the driver's side injectors) and crank until you have fuel dripping from the lines. Tighten up, reinstall glow plugs, and give it a shot. The reason for removing the glow plugs is so that the engine spins faster. You can do it with the glow plugs in, just don't crank for more than 30 seconds at a time and you will probably wear down the battery.

[a5150nut]

Are your batteries up in top shape?

Your truck has to get to 100 rpm cranking before the pump will let the injectors have any fuel.

[Josmuck]

Hi All,

Thanks for the help here!

Well the injectors are loose, at least on the driver’s side and still nothing! I talked to a old Army mechanic and he
Has a trick I should try!

Use a rag and the compressor hose and pump air into the tank, at the same time have somebody try to start the
Truck! If for some reason there is air in the system this should push enough diesel thru the system to get it going!

Cya Brian

[Josmuck]

BTW the batteries are new and the glow plugs from the driver side are take out.

[Robyn]

Forget the rag and air hose, as this will not help and may cause damage to the tank, hoses etc.



If you are getting fuel to the IP from the tank (Lift pump working) you have issues at the IP.

Disabling the fuel shut off solenoid is not something you want to do.

If the engine starts and things get out of hand (run away) there is no way to shut it off.

I reread your previous posts.

This issue could very well be a failed PMD (Pump driver module/black box on side of IP)

Make sure that the electric lift pump is working and supplying fuel.

A failed oil pressure switch will foul things too and keep the lift pump from working.

Switch is located near the LH rear of the engine behind the intake manifold.

If you get a good stream of fuel to the IP when the engine is cranked (hose in a can) this is a good thing.

If cranking does not get fuel to the injectors then the issue is likely the PMD

Please be safe and get a proper fuel shut off solenoid in the IP before continuing the process.

As I mentioned earlier, without a working solenoid the engine can't be shut off in the event of a internal electronic control failure that results in a full throttle run away.

The PMD is a known failure point.

The PMD also requires a little resistor chip that slips into the plug socket on the PMD
The one that's in the current PMD can be coaxed out and reused in a new PMD.

I'm not sure of your parts availability in Germany, but the NET can be a great source of parts such as a PMD (DTECH is a good brand and plugs right in)



Fix the shut off solenoid and make sure it Clicks when ign is turned on.

Be sure of fuel flow to the IP while cranking.

Replace oil pressure switch

PMD is always a prime suspect in a no start condition.

Keep us in the loop.

Be safe

Robyn