Marine engine firing order is designed to distribute the engine power on the crankshaft bearings evenly. It should also be the optimum firing order to ensure the least engine vibration through balancing the power output along with consideration given to torsion and axial characteristics.
The Importance of Correct Firing Order to a Marine Diesel Engine are:
- Engine Vibration
Torsional Vibration – caused by the reciprocating components, this is a highly undesirable condition in a marine engine. Not only for the comfort of passenger and crew, but also for the durability of the engine through undue fatigue.
- Engine Balance
Imbalance of components is once again the cause of fatigue of the rotating components, especially the crankshaft. It is imperative that the firing order compliments not only the balancing of the components, but balances the power output from the cylinders spreading the load over the length of the crankshaft.
- Gas Forces
Enormous gas forces are produced in the cylinders on the compression/firing stroke. These create individual cylinder torque characteristics that are transmitted downwards into the engine block, and bedplate via the main crankshaft bearings.