Truck Repair: cummins engine, cummins engine, drive pulley

Question
i have a komatsu motor grader equiped with cummins engine. it is 855 engine there is no number plate on it. and no mark on acessory drive and damper.
my question is how to come to know about what type of engine it is.i mean nt nta or stc. the injector installed are without flange.
2nd how may i adjust valve lash and injectors on it.
please advise
thanks  

Answer
There has to be 4 "notches" on the inside of the accy drive pulley to adjust the valves.There should be a serial number on the fuel pump side at the rear of the block near the rear intake port.There is a boss there with the serial number stamped in it.