You might want to try this first
I removed my injection pump-Injectors and had them cleaned. When I went to crank it, nothing for MANY days and I worked on it every day. I Then pulled the injectors out reattached the fuel lines with then injectors out of the head so I could SEE if they where bled. One was one wasn't. Now I knew it was a bleeding problem,I put it all back together bled again still wouldn't crank. (Below is what I would do, forget removing injectors and fuel lines as that was just a time consuming test) So I bought a remote switch that connects to the starter so I could turn it over inside the boat, Now I could turn the motor over and at the same time I could spray the wd40 in the intake.(DIESELS WILL RUN ON WD40) It started to "try" to start, so kept doing that and it did start but ran REAL ROUGH. I thought about it for a while and I started it again and while it was running rough I cracked open the fuel lines to each injector, one damn near killed it so I closed that one and cracked open the other-no change so I left it open till the fuel REALLY started spraying-Tightened the line and it ran GREAT! Keep in mind, It will run REAL ROUGH at first as in the motor will kind of jump around but have faith it will bleed. Long story short, it is hard as hell to bleed the high pressure pump (fuel distributor) so you might as well let the motor/wd40 do it. By the way I didn't just make this technique up I read about it on Torrenson Marine, the poster had the same problem I had and you have now but he just posted the problem but not the answer so I emailed him and he wrote me back that answer. There are only three things that Diesels need to run Fuel-Compression-Air. I assume your air intake is clear, and your Compression is fine (new head gasket)and it ran fine and then just wouldnt start, which leaves fuel. You probobly lost prime some kind of way which needs to be checked or it may do it again. One more important thing, when you installed the High Pressure Fuel pump did you make sure the fuel rack went into the throttle linkage? If not you will not get enough fuel to start the motor. The only other thing it could be is that your "mechanic" did the valves wrong and it has no commpression but you would be able to tell that as in the motor will turn over real easy. I hope this helps.
