88 2.9 starts and dies. fuel issue?

[machinist]

hi all, I recently purchased this beautiful 88 2.9 5 speed 2wd from my brother who only owned it for about a month. the kid he bought it from, drove it for about 2 years and then had an injector problem so he replaced the injectors with brand new injectors and the truck ran fine for a week before it got to the condition where it is in now....(one thing the kid said is that he had rust in the injectors and thought that the injector manifold was too rusty so he sprayed some sort of blue adhesive into the manifold in attempt to try and seal the rust)

When i start it, it will run for 1-10seconds and die. my brother took the rear tank(front tank has a leak) pump and sending unit out and everything checked out fine. he replaced the fuel filter and nothing changed. he checked the fuel pressure and says it is to spec.

I pulled the fuel rail "manifold" and injectors to take a look and found that indeed the fuel in the manifold was darker than it should be and dripped it onto a paper towel to see what it would look like when it dries and it left big rust colored spots. i found the return line was almost completely blocked off by that spray adhesive. so i cleaned what i could and reassembled the truck and the condition did not change.

I found a performance shop that specializes in tuning that will bench test the injectors and return them to new condition if they are clogged with rust or blue crap for 70bucks. i found a junk yard thats 3 hours away that has 3 2.9s in their lot and says they will pull a fuel rail for 28 bucks( i told them to go for it 5 days ago but have not heard back from them)

I am not afraid of spending 100 dollars on this truck because i paid only 300 for it! however i want to be certain that im heading in the right direction and not just throwing money at it unnecessarily.

Please let me know what you all think.

-rob

 

[voodoochylde]

Check fuel pressure while running, both at idle and when you goose the throttle. Shut it off and then check fuel pressure with engine off after about half an hour.

If pressure has dropped significantly, this can tell you if the check valve in the high pressure fuel pump on the frame rail (just forward of the transfer case) has failed. If so, it can lose pressure and take 2 or 3 starts before it will stay running. The check valve is integral to the fuel pump assembly and can only be serviced by replacement of the pump.

 

[RonD]

Yes, check the high pressure pump in the frame rail by the filter.

There may also be a Reservoir in the frame rail a little farther back towards the tanks.
Looks like a screw cap filter that uses a cartridge, but it is just a reservoir, and could be clogged.
Dual tank image here: http://tse2.mm.bing.net/th?id=OIP.M1bd4a7dc1e0d1a9cd2d421fc549fefeco0
This one may also be a filter

The fuel pumps in the tank are low pressure "lift" pumps for carb engines, for fuel injection a high pressure pump needed to be added, that pump is in the Frame rail.
What Ford did was to Splice that pumps 12volt wire into the in-tank pumps power wire running back to to tanks.
That splice often corroded causing high pressure pump to stop working.

Lift pump might get engine to start, but it would die quickly if high pressure pump wasn't working, which is what you describe.
Fuel pumps will run for 2 seconds each time key is turned from OFF to ON.
Have some one turn the key on and off while you feel the high pressure pump, to see if it is working, if not, then that's the problem, trace wire back to splice, it is very close to this pump.
If splice looks OK then check that pumps Ground wire to frame.
And as last resort run a 12volt wire back to that pump and see if it powers up, if not replace it

 

[machinist]

I will try to rule out the high pressure pump, and the fuel reservoir before i have the injectors cleaned and replace the fuel rail.