Ford 555c air out of the injector pump

[mic-t]

92, 555c I have air in the lines at #4 injector line out of the back of the injector pump but its only #4 when I crack the lines on 1-3 the engine sputters with no air just fuel . when I crack the fuel line on #4 engine does not change and I get fuel with lots of air, is the pump bad ? I am stumped!!! I did just replace the fuel shut off solenoid.

 

[Dieseltech]

Remove the injection line at the injector and crank engine with the starter, there should be NO compression air blow back out the injector line inlet. If it does that
injector tip is stuck OPEN, and WILL cause the trouble you describe. Injector needs repaired/reset with a new tip installed.

 

[mic-t]

wow I would have never thought about the air coming from the injector but that makes sense that its just one line. I just put new injectors in it and have about 5 hours on them. I will check that this evening.

 

[Hemmjo]

Interesting, I never thought of that happening. Good to know for future reference.

 

[Dieseltech]

I've seen it happen several times in my nearly fifty years of diesel injection service. First time was years ago on a Case 1030 with the Bosch inline injection pump, the number three pump outlet line had lots of air with the line nut loose at the pump. Injector was stuck open allowing compression air to blow back through the line when nut was loose. A repaired injector with new tip cured the trouble.

 

[mic-t]

Well if its going to happen its going to happen to me. Ill update when I get it replaced.