MrSuzuki

What Happened:
Had to brake kind of hard from 60 mph for a red light, came to a stop, and noticed the engine had died. Knew something was wrong, as this has never happened. Have not been able to start it since. Truck ran perfect up till this point.

What I have Checked:
Fuel shutoff solenoid is working properly. Plunged fuel up through the bleeder on the fuel filter...seems to have fuel there. Removed number one cylinder injector line at injector...no fuel. Removed number one cylinder injector line at injector pump...no fuel. Why would I suddenly not get fuel to the injector pump?

What next:
1. Overflow valve?...could this prevent fuel from getting to the injector pump?
2. Fuel filter plugged instantly...only 5000 miles old.
3. Lift pump instantly failed?....thought you can still start with a bad lift pump.
4. Is it possible the timing could have slipped to the point that the drive gear is not turning the pump?...I know, hard to believe this is possible.

I am selling this truck, and I am just stumped on what is going on...this truck has never had a problem...always rock solid performer.

Thanks

Dartmouth 12V

Sorry I have to ask, are you sure that there is plenty of fuel in the tank? When you cracked the bleeder screw, were there any bubbles or was it straight fuel?

When you checked the shutdown solenoid, did you also check the linkage that it connects to? It is possible that this could have broken.

I doubt that it is your fuel filter since a plugged one will result in reduced power at WOT long before it is a problem at lower rpms.

There is the unfortunate possibility that something is wrong internally to the IP.

MrSuzuki

Yes there is 3/4 tank of fuel.

The first pump or two of the plunger, produced a couple bubbles out of the bleeder screw....but then solid fuel. I suspect the air was created when I loosened the bleeder.

Linkage on the exterior of the pump is all attached. I don't know what lives inside the IP...it is acting like whatever is attached to the shaft inside the IP, is not working correctly.

IP failure?...hard to believe it just quit....without warning, so I am not on that page yet.

I checked the overflow valve, and I have fuel up there. First pump of the primer, and fuel seeped out when it was cracked. So I am ruling this out.

I removed the number one delivery valve, hooked up my SnapOn indicator for setting the timing, and the plunger is moving, so I know it is still connected to the gear inside the timing cover.

I can't help but to think whatever the shutoff solenoid linkage is connected to (shaft) has broken inside the IP???? And preventing fuel from getting into the IP, because there is still no fuel coming out of the IP, at the number one delivery valve, with the line detached.

It is acting like the IP is not getting fuel...yet everything that is to provide the IP with fuel, appears to be working.

John Faughn

Did you get to the clutch peddle before the stop [ or did the truck not rolling and still in gear make the engine stop ] ?
Next , when you pump the primer/lift pump , is there a buzzing sound after some pumping ?
There should be the buzz , that's the overflow ball bouncing off the valve when the LP gets to enough pressure to get past the spring .
Check the fuel pressure with the lift pump , its possible that the hoses gave up [ if old ] at the sudden stop , sucking air , put 2-3lbs of air pressure in the fuel tank to check hoses , normally a vacuum so no fuel leak to see without the pressure .
Then move on to more complicated possibilities .

MrSuzuki

Good question about the clutch. I have gone over and over this in my mind, and I think that maybe I did not clutch it, until I felt the truck chugging, which I then pushed in the clutch....and this is when I looked down and saw the engine had stopped. Why?...what are you thinking?

The primer causes more of a squeak when I pump it, rather then a plunge. It is a squeak that sound more like air, then fuel....but when things are running, you don't test these things, so I don't know what it should sound like. I did crack the valve at the banjo fitting, and immediately got fuel with a pump. So I don't know"

I will check the hoses...with some air pressure in the tank.

I agree, eliminate the easy stuff first. Can't get it out of my head...what causes an engine to stop running, when it was just running perfectly...and then not allow you to start it? It has something to do with braking hard...and I can't figure out what. This was the last thing the truck was doing, before the engine stalled.

Dartmouth 12V

The only things that I can come up with are a sudden air leak or internal pump problems. If you are getting solid fuel, then it probably isn't an air leak in the fuel system.

You say that you aren't real familiar with the internals of these pumps? Do you have any buddies that are and would be willing to tinker for a few beers?

MrSuzuki

I am familiar with the afc, plate, governor spring...but not much past that. As for buddies?...I am usually the guy they come to...this is why I find myself really stumped on this one.

I am going to have to start at the tank...work my way forward, and see what I find. Nothing I can think of, is caused suddenly. Air in the system is noticeable with hard starts....not my case...always started on a flick of the key. Injector pumps begin losing it...they don't just quit. Filters the same. Even the lift pump or dirty prefilter screen, usually give you some warning.

When it happened, I was convinced it was the shutoff solenoid....but not the case.

I am still curious why I was asked if I let the engine stall without pushing in the clutch...not sure why I was asked this....does this somehow cause something related to the issue I have?...don't know.

infidel

I had a return line suddenly bust open, lost a full tank in about 20 miles. Truck ran fine but I don't see why a supply line couldn't do the same thing stopping you dead. You wouldn't lose any fuel but could be sucking a ton of air.

Lil Red

This probably won't help the matter but on my truck I wasn't getting any fuel and the problem was the supply line had small cracks in it. When I pumped the fuel pump I could here a air squeaking noise which was air being sucked in.

Tate

Take the AFC off and the plate out. Operated the shut down lever, you should see the gov arm and rack moving. If not that, then you have an internal problem. Conversely, you can pull your DV out again and make sure the plunger will rotate inside the barrel when you move the throttle. The shut down lever must be up for this. If you move the lever up and down, the plunger will also rotate. No rotation means that the rack isn't moving, so you have no throttle control. Also, while you have the DV out, if you prime the lift pump, you should see fuel coming into the barrel. If you have bubbles, you obviously have air in the system.

MrSuzuki

Alright...I have a Sunday's worth of work.

Tate??? If I find that after taking off the afc and removing the plate....something is wrong internally....is that it? I need to pull the pump, and get it rebuilt and/or repaired...or can the pump be repaired while in the truck. Also, I have always been under the impression these P-pumps are pretty bullet proof....so is it common to find something go wrong internally, or is it quite rare.

I know....just go look....I will on sunday...only day off. Just curious, as I am hoping for a blown rubber hose from the fuel tank...to be the cause of all my frustration.

Tate

P-pumps are quite robust. That being said, they are mechanical, and can and will fail at one point or another. Failures are typically rare, so chances of a stuck rack is not likely. Just something to investigate to rule out the IP and focus on the low pressure side of the fuel system. If you do wind up with a stuck rack or stuck plunger, then I'd suggest taking it off and having it rebuilt. I'm no expert on these pumps, so I wouldn't suggest taking it apart further unless you know what you're doing.