OVERHAULING (dismantling and assembling) CYLINDER COVER IN MAIN ENGINE on ship

SAFETY PRECAUTIONS

-On FWE get immobilization permission and propeller clearance from bridge.
-under piston spaces and scavenge space ventilate by blower.
-Stopped engine
-Shut off starting air supply At starting air receiver
-Block the main starting valve
-Shut off starting air distributor/distributing system power supply
-Shut off safety air supply
-Shut off control air supply
-Shut off air supply to exhaust valve – Only with stopped lubricating oil pumps
-Engage turning gear
-Shut off cooling water
-Shut off fuel oil
-Stop lubricating oil supply
-Lock the turbocharger rotors
-isolate expansion tank than only drain jacket drain jacket cooling water and open purging valve so that air pressure helps in draining.

TOOLS REQUIRED -
Grinding tool for exhaust valve seat,Milling and grinding wheel for fuel valve seat,Milling and grinding wheel for starting valve seat,Grinding handle,Cylinder cover tightening tool,Cylinder Cover - Lifting Tools,Hydraulic pump, pneumatically operated,Hose with unions (1500 mm), complete,Hose with unions (3000 mm), complete.

Shut off Oil and Water Supply

1. Check engine blocking.
Check that the engine is stopped and blocked according to the safety precautions given on the data sheet.

2. Shut off the oil supply.Close the fuel oil supply for the unit concerned.
3. Shut off the water supply.see fig 3
-Close the water outlet above the exhaust valve.
-Close the water outlet on the exhaust side of the cylinder cover.
-Shut off the water supply placed on the exhaust side below the exhaust gas receiver.
-Open the drain next to the inlet valve.
-Open the venting cock or purging valve next to the outlet .so that air pressure helps in draining the water.

Dismantling of Pipe Connections

4. Disconnect the oil pipes.
-Remove the hydraulic high pressure pipe for the exhaust valve. See Procedure.

-Unscrew the drain pipe for the exhaust valve.
-Remove the fuel oil high pressure pipes.See Procedure.
-Disconnect the pipes for return fuel oil from the fuel valves.
5. Disconnect the water pipes.Unscrew and remove the water outlet pipes.
6. Exhaust gas compensator.
Remove the protective jacket enclosing the insulation for the intermediate pipe or compensator. Remove the insulation.Remove the screws in the flange between the intermediate pipe and the exhaust receiver.

7. Disconnect the starting air pipe.
Unscrew and remove the control air pipe for the starting air valve.Unscrew and remove the air pipe for the starting valve.
8. Cylinder cover loosening.Remove the protective caps from the cylinder cover nuts.Loosen and remove the cylinder cover nuts, see Data.For use of hydraulic tools, see Procedure
9.Cylinder cover lifting.

Hook on the engine room crane to the lifting attachment on top of the exhaust valve.Check that all cylinder cover connections
have been loosened and removed.Lift away the cylinder cover complete.

10.Cylinder cover landing.see diag
Land on a couple of wooden plan.

11.Remove sealing ring.
Remove and discard the sealing ring between the cylinder cover and cylinder liner.

Overhaul Preparations

1. Dismantle valves and pipes.
-Dismantle all valves and pipes from the cylinder cover. See Procedure
-Dismantle the starting air inlet block and the cooling water outlet block from the exhaust side of the cylinder cover.
Remove all studs on top of the cylinder cover.

2.Cooling Water Jacket

2. Remove the cooling water jacket. Mount four eyebolts and the lifting chains as shown in the sketch. Remove the four screws which secure the cooling jacket to the cylinder cover. Lift the cylinder cover free of the cooling jacket and land it on a couple of planks. Remove and discard the O rings from the
cover, and carefully clean the cooling jacket and the cylinder cover.

3. Mount the cooling water jacket.
Provide the cylinder cover with new O rings, well lubricated with oil. Lift the cylinder cover and guide the jacket/ cover into position, using the guide pin as a reference (manoeuvre side). Fit and tighten the screws for the cooling jacket.

Reconditioning of Bores

4. Seat reconditioning tools.
The tools for reconditioning of the valve seats are found on tool panel.

5. Fuel valve bore.
The tool consists of a common spindle with a handle, a guide, a carbon cutter, a seating face cutter and a grinding mandrel.
Clean the fuel valve bores using the carbon cutter. If required, recondition the fuel valve seating with the appropriate cutter.
Grind the seating with the grinding mandrel and a grinding compound (e.g. Carborun-dum No. 200). After the milling/grinding, clean the bore and seating carefully, and check that the seating is not damaged.

6. Exhaust valve bore.

7. Starting valve bore.

8. Indicator safety valve bore. Clean the bores for safety valve/indicator

Preparations before Mounting.

9. Fitting of studs.

Lubricate the threads with ‘Never Seize’ or molybdenum disulphide (MoS2) and fit the valve studs.Tighten up the studs in accordance with the screwing in torque stated on the data sheet.
Fill up the grooves between the valve studs and the bores for the valve studs with permatex to prevent water or oil from entering the bores during operation of the engine.

10. Mounting of valves.
Install the valves on the cylinder cover, see Procedures.

Landing Preparation

1. Sealing ring.
Check that the liner sealing surface is clean.Place a new sealing ring on top of the cylinder liner.If necessary fit a new ‘klinger’ sealing ring in the groove of the flange of the intermediate pipe.

2. Water connections.
Check that the water connections are clean and provided with new O rings. Lubricate the O rings with Vaseline and fit them on the cylinder liner.

Cylinder Cover Mounting

3. Cylinder cover landing.
Lift the cylinder cover by means of the crane and lower it carefully into position. During the landing, carefully check that the cooling water connecting pipes engage correctly with the holes in the cooling jacket.

4. Cylinder cover stud check distance.
If the cylinder cover studs have been re- moved and reinstalled, check the distance the stud is protruding from the cylinder
cover. If necessary, adjust to the distance D01 05
by turning the stud

5. Cylinder cover tightening.
Fit and tighten the cylinder cover nuts.For operation of hydraulic jacks, see Procedure 913 1. Fit the protective caps on the cylinder cover studs.

Fitting Pipe Connections

6. Mount the exhaust gas compensator. Fit the screws of the flange between the intermediate pipe and the exhaust receiver.
Fit the insulating jacket around the intermediate pipe.

7. Connect the starting air pipe.
Connect and tighten the air pipe for the starting valve.Connect and tighten the control air pipe for the starting air valve.

8. Connect the water pipes.
Mount and tighten the water outlet pipes.

9. Connect the oil pipes.Mount the hydraulic high pressure pipe for the exhaust valve. See Procedure
-Connect the drain pipe for the exhaust valve.
-Connect the fuel oil high pressure pipes.
-Connect the pipes for return fuel oil from the fuel valves.
-Open Oil and Water Supply.

10. Close the drain and open the water supply.Close the venting cock next to the outlet valve. Close the drain next to the inlet valve.Slowly open the water supply valve, placed next to the cylinder liner cooling water jacket on the exhaust side.Vent the unit by releasing air through the venting cock next to the outlet valve.
When the venting is finished, close the venting cock. Open the two water outlet valves on the exhaust side of the cylinder cover.

11. Open the oil supply.
Open the fuel oil supply for the unit concerned.