Cylinder do not fire :
1.The shut off valve on the fuel supply pipes or before the fuel filters are closed .
2.Insufficient fuel supply pressure .
3.Fuel is either unsuitable or contains water.
4.The fuel pump chamber or delivery pipe have been only insufficiently primed or not at all , and contain air or fuel vapour .
5.Compression pressure is too low .
6. The quantity of injected fuel is insufficient .The speed adjusting lever should be moved to a some what higher position .
7.The regulating linkage or one or more eccentric shaft stuck .The load indicator should be checked .
8.The governor moving arms sticks in an extremely low position and releases only an insufficient fuel charge or none at all .
9.One of the control element is stuck ,the cut out servomotor does not release a fuel charge .
10.The fuel pump plungers are either raised or seized.
11.The fuel pump valves are either leaking or stuck .
12.The safety governor has tripped and fuel pump suction valve remains constantly open .
13.The fuel valve nozzle are either obstructed or defective or thheir needles are stuck.
14.The priming pump of the fuel valve open or leaking .
15.Lube oil pressure or cooling water pressure is too low .the automatic cut out device does not release fuel supply .
Possible causes for :INDIVIDUAL CYLINDER DO NOT FIRE CORRECTLY :
1.The fuel pump drive of the cylinder in which is not firing is still raising or the fuel pump plunger is stuck .
2.The fuel pump or fuel delivery pipe of the cylinder which is not fired has not at all or only insufficient been primed and still contains air or water .
3.The suction or delivery valve of the fuel pump is leaking or stuck.
4.The relief valve of the fuel pump of the cylinder which is not fired is leaking or fully lifted .
5.The priming plug of the fuel valve is still open or leaking .
6.The fuel delivery pump is leaking .
7.The fuel valve nozzle is obstructed or leaking .The nozzle needle is seized .
8.The compression pressure is too low for firing .
These are the case where the individual cylinder does not fire as an engineer you should be able to identify the fault and correct it as you know the trouble shooting of the engine cylinders which is not firing .