Just to let everyone know what Ryderfzr and myself did this evening to get this no start issue squared away. Since he was 100% sure that the cam/IP/crank timing was dead on we moved into finding out why the fuel lines were full of air. Looking at the slight fuel moisture/dirt buildup on the front of the IP it was immediately apparent that like most older IP's it had developed a leak. IP fuel return lines look to be in new condition so no issue there. We had an unknown replacement history on the fuel filter, so we went ahead and changed it and the two O rings on the thermostatic Tee. We used some Hylomar non setting fuel resilient sealant on the O rings and on the fuel line connections to ensure no air would enter through that path. We tried to prime the fuel filter, and it seemed like fuel wasn't flowing as freely as I believed it should have. We inspected the fuel tank sender unit for restrictions in the check valves and found one that could have possibly been plugged up. After doing the fuel sender check valve drill out mod we went ahead and tried priming through the fuel filter again, and fuel was flowing very freely this time. Since we knew we had free flowing fuel up to and through the fuel filter we tried to prime the IP from it's outlet line. The thought was to get the IP full of fuel and that would help us to get the injector lines bled out easily.
We found that we were sucking air from one or more of the IP seals, and given the traces of fuel and dirt on the front side of the IP this makes sense. In a valient effort we checked the operation of the fuel shutoff solenoid, and replaced it's O ring, and checked the case pressure relief valve to make sure it's guts were where they should be and replaced it's O rings too. We also verified we had 12 volts to the solenoid, and heard the audible click as it engaged. Since we seem to be having major air intrusion issues through the IP seals I recommended he puchase a Dieselgeek IP reseal kit, and also the seal for the high pressure head.
Only thing I wished that we would have tried was to plug off the fuel return nipple on the IP, and try to prime the pump again-it is possible that even though the fuel return lines look new they could be allowing air to enter. Hind sight is 20-20, but in this situation given the evident fuel leakage from the IP, the IP seal replacement is a wise move.
Did I miss anything on the diagnosis/trouble shooting?
