Operational Faults Due To Faulty Oil System

a) Insufficient Oil Pressure in crank case Lubrication:

As we have discussed earlier that the oil pressure has to maintained for the proper lubrication in the Marine Diesel Engine. As the lubrication fails it give rises to the operational faults ultimately failure of the system and the bearings in crank case

Possible causes:

1.Defective oil pump.

2.Inadequate delivery rate of the oil pump. The prescribed delivery rate should be adhered to.

3.The by-pass in the installation is opened too far.

4.The oil regulating valve is not opened far enough.

5.Excessive bearing clearances.

6.Defective oil supply pipes.

7.Defective crosshead lubrication system.

8.The oil level in the tank has fallen too low. The oil pump is drawing-in air.

b) Crank case Lube Oil supply is interrupted:

As we know the oil flow should not be interrupted by any means if it does it result in the Operational faults.

Possible causes:

1.Oil passage or grooves are obstructed.

2.Defective oil supply pipes.

3.There is air in the oil supply pipes.

Possible causes:

1.The non-return valve for the lubricating stud is defective.

2.The cylinder oiler or its driver is defective.

3.Lubricating oil pipes or pipe connection is defective.

4.Lubricating oil pipe, or cylinder lubricating studs, is defective.

5.The cylinder lubricators need replenishing.

6.There is air in the piping.

a) Fault in : Preheater, Filter, and Fuel pipes remain cold as a state which applies particularly to operation on heavy fuel oil.

Possible causes are :

1.No steam pressure.

2.Steam pipes obstructed.

3.Failure of the steam pressure-reducing valve.

4.Condensate accumulating in the heating pipes.

5.Water accumulation in the steam trap.

6.Inadequate venting of the heating pipes.

b) Fault in : Fuels do not Circulate and Unheated portions remain cold: A state which applies particularly to operation on heavy fuel oil.

Possible causes are:

1.Fuel circulating pump is defective, or out of service.

2.Fuel tank is empty.

3.Fuel cannot be pumped because of inadequate heating.

4.Shut-off valves or change-over cocks, before or after the fuel circulating pump, are either closed or else set wrong way.

5.Fuel pumps inadequate vented.

6.Fuel pipes clogged by congealed fuel. When the fuel delivery pipes are obstructed, the engine should be barred over with the turning gear for several revolutions, with maximum fuel charge and the priming plug open.

7.Individual fuel pipes inadequately heated or not heated.