Engine/Transmission (1994 - 1998) wont shut off(engine)

[love-horsepower]

i posted under wont start and that was true but now it will start but wont shut off and the intercooler is not full and the solinoid is not hanging up it is something inside the injection pump can the fuel plate come lose and go the wrong way because it wasnt to go to 38-3900 rpm with out the turbo hose hooked to the intake i can move the throttle ore the fuel shut off lever either way absolutely no change the only way to shut it off is to cut the air.

 

[snappy]

It would be possible for the fuel plate hold down bolts to work themselves loose, but only if they were not tightened enough to begin with. Remove the 4 bolts that hold the afc cover and verify that all is well with the plate. What happens when the truck is started up? Does the rpm go to 3800 without touching the throttle? John

 

[love-horsepower]

yes even with the fuel shut off disconnected it starts and goes to 3800

 

[snappy]

Has the injection pump or governor been recently worked on? This sounds like a governor issue.

 

[Missouri Mule]

I agree the governor could be messed up but when the fuel shut off solenoid rod is in the down position no fuel should be getting to the p7100. I would take the fuel shut off solenoid off make sure it working and conected properly.

Make sure rod is adjusted correctly.

 

[Joe G.]

It sounds to me like there is an internal pump problem or a governor problem. The fuel shut off solenoid does NOT operate a valve. There is still fuel flow to the P7100. You can prove this by operating the push button on the lift pump. When you do that you can hear a squeak from the overflow valve.

 

[love-horsepower]

it is still getting fuel i cracked injectors and it was spraying fuel i also opened the drain for the water seperator as it was running with the fuel shut off soliniod down and by pumping the priming pump i hear a squeak as fuel is pushed by the by-pass regulator. the govenor or anything on the injection hasent been changed for the last 50000 that i have had the truck.

 

[Missouri Mule]

But many members have had problems with engine performance when the Fuel

Shut Off soelnoid wasn't opening all the way so it does limit fuel to the p7100 and to rev to 3800/3900 rpm it has to be open all the way.

 

[Joe G.]

I don't know exactly how it works, but it does not shut off fuel to the P7100 because it still flows through the pump if you use the push button and the fuel solenoid is down. Fuel has to flow through the pump to lube the injectors when the engine is turning but not running. I have asked some experts if it does something with the rack to not allow the plunger to push any fuel to the injectors. I'm told that's about right, but I don't know how it does it. I had a Buda marine diesel in a commercial fish boat that was made in 1942. The IP looked just like the P7100 except it had four instead of six and the governor was different. The pull cable to kill the ending pulled the rack back past the idle position so no fuel went to the injectors. It did that directly. From what I have been able to find out the P7100 uses a "spud" in some way to do that. Maybe someone who knows exactly how the pump works will chime in here.

 

[love-horsepower]

i a shure you that it was all the way closed as i moved it up and down with the switch off. that is the fuel shut off lever.

 

[Missouri Mule]

love-horsepower, there is a possibility that the rod is misadjusted or it came off the lever of the p7100 leaving the lever in run position.



Joe G. Becaus it was slow at my business today (rain off and on) I did a little experimenting. I disconnected the fuel shut off connector then cranked the engine naturally it did not fire up. I then pushed the prime button until (and a few after the fact) I heard a squeak, I cranked the engine not to my surprise the engine did not fire up. I reconnected the fuel shot off connector and cranked the engine, it fired up.

How the fuel gets by the without the rod being up I don't know but the rod has to be up and the lever(part of the p71100) has to be a run positon for the engine to fire up (or at least not in shut off position).

 

[Joe G.]

I'm not sure what your point is. That's the way it's supposed to work. When the rod is up the lever is doing something inside the pump, but it's not opening and closing a valve. It's doing something with the rack just like the old IP I had on the Buda marine diesel. That one parked the rack so that the port for each barrel would not close. That caused fuel to pass through the barrel without being pressurized. In normal operation the plunger covers a port so that it can compress the fuel to cause it to pop open the injector. As the plunger goes up it will uncover a port so the pressure will leak down and the fuel to the injector will stop. Rack position controls when that happens. If the ports are never closed that cannot happen, but there will be fuel flowing in the pump to keep the barrels and plungers lubricated. That's what is happening, but I don't know exactly how is it done in the P7100.

 

[love-horsepower]

i wish that mine would start in the up or run position and off in the down or off position but that is not the case with it . it runs wild with it down and no matter if i lift it up move the throttle fast or slow it just sits there screaming away at 38-3900 rpm till i block the air!

 

[Joe G.]

You may have something broke or disconnected in the pump so the lever can't do it's job.

 

[Missouri Mule]

love-horsepower, pull your "fuel shut off solenoid off" and make sure lever is not in run position just to rule it out.

Running up to 3900 rpm is probalby an internal problem wilth governor or p7100.

 

[love-horsepower]

done that multiple times.

 

[Missouri Mule]

love-horsepower, I take it you have checked oil level make sure the engine isn't using it to run off of.



If oil level is fine (which I'm sure it is). Then you will have to pull the P7100 (or diesel shop) and have it looked at (since you have pulled the solenoid off and checked things out).



You will need to check for broken/loose springs in the governor or have injection pump shop do it( I believe if you broke/loose a spring this would allow the engine rev to 3900 rpm instead of the 3000 it is supposed to (usually from 2400 to 2900 rpm is average depending how lucky one is).

 

[Joe G.]

I think that there is more wrong than governor springs. If the shut down lever was preventing fuel from going to then injector lines then it would die normally as soon as the fuel solenoid dropped in spite of the governor springs.

 

[Missouri Mule]

I agree there is something wrong inside of the p7100 injector pump causing it not to shut down in which case it has to be removed taken apart and looked at and fixed.

But the governor dictates how high the engine revs so there is the posiblilty that a spring is loose or broken but the problem could be also inside of the p7100 for high revs. It is not that hard to get a look at the springs and it mite save him some money.

 

[SFPADGETT]

Just came across this thread. I know it has been a while, but here is another possible problem to the run wild. # 1 Delivery Valve on the P7100 pump, the bottom half was installed upside down (usually happens after you adjust the timing and had # 1 out for the gauge). When installed upside down the fuel shutoff solenoid will NOT shut down the engine, only stopping the air or disconnecting a fuel line will.



Dont ask how I know this, but I do.