Truck Repair: problem about valves and injector, screw out, cummins l10

Question
I want to know about how to adjust the valves and injector of Cummins L10.
Problems: the truck does not have power.  

Answer
The L-10s adjust the same except for the STC ones.The only difference is the STC injs you have to hold the inj tappet up to set the "ZERO LASH" clearence.A is 2 or 5 valves & 3 or 4 inj,B is 3 or 4 valves & 6 or 1 inj,C is 1 or 6 valves & 5 or 2 inj.Lash is 0.014 & 0.027.The Celect ones you bottom injector slightly & back screw out 2 flats & lash is the same.The only difference is A is 1 or 6,B is 2 or 5,C is 3 or 4 valves & inj adjust on same cyl.