Main Engine Liner Removal Procedure for S50MC-C Engine

Cylinder Liner in any marine engine is an integral part of the combustion chamber through which power is generated. Like all other machineries and engine parts on ships it also has to be overhauled after specific interval as described by the engine makers.

Previously we have discussed Reasons for Cylinder Liner wear and ways to measure it, in this article we will discuss the liner removing procedure of MAN S50MC-C engine.

Following Procedure has to be followed when opening Liner of S50MC-C engine:

 1)    Inform company and take permission.

2)    Take immobilization certificate from port state control.

3)    Read the manual and have a tool box meeting with everyone involved in the job. Discuss the complete procedure.

4)    Prepare important tools and spares required for overhauling liner as given in the manual

5)     Prepare risk assessment and make sure all personal safety equipments are used

6)    Shut starting air for Main Engine and display placards

7)    Engage turning gear

8)    Open indicator cocks for all the cylinders

9)    Stop main lube oil pump and switch off the breaker

10)  Drain the jacket water from exhaust v/v and liner.

11)  Shut the fuel oil to the particular unit whose liner is to be removed

12)  Dismount the cylinder head using dedicated lifting tools

13)  Discard the sealing ring from top of the cylinder liner.

14)  Turn the piston down far enough to make it possible to grind away the wear ridges at the top of the liner with a hand grinder

15)  Dismount the piston by following the procedure given in Manual

16)  Mount the 2 lifting screws in the cylinder liner.

17)  Disconnect the cylinder oil pipe connections. And screw of the non return valves.

18)  Dismount the four cooling water pipes between the cooling jacket and cylinder cover and clean them carefully.

19)  Remove the screws of cooling water inlet pipe.

20)  Attach the crane to the lifting tools.

21)  Hook the chain from the lifting cross bar on the lifting screws and lift the cylinder liner with the cooling jacket out of the cylinder frame.

22)  Place the cylinder liner vertically on a wooden plank.

23)  Clean cylinder frame internally paying special attention to the contact surfaces for the cylinder liner at the top of the cylinder frame.

24)  Discard the O-ring on the cooling water pipe.

25)  Clean the pipe carefully.

Make sure to inspect the liner for cracks and other defects.