Disassembly And Reassembly; Disassembly - Yanmar 3YM30 Service Manual

4. Disassembly and reassembly

4.3 Disassembly and reassembly

4.3.1 Disassembly

• Preparation on a boat
For engines mounted in an engine room of a ship, remove the piping and wiring connecting them to the
ship.
1) Remove the remote control cable (from engine and marine gearbox).
2) Unplug the extension cord for the instrument panel from the engine.
3) Remove the wiring between the starting motor and the battery.
4) Remove the exhaust rubber hose from the mixing elbow.
5) Remove the rubber hose connecting the coolant recovery tank to the filler cap.
6) Remove the seawater inlet hose for the seawater pump (after making sure the seacock is closed).
7) Remove the fuel oil inlet rubber hose from the fuel feed pump.
8) Remove the body fit (reamer) bolts and disassemble the propeller shaft coupling and thrust shaft
coupling.
9) If a driven coupling is mounted to the front drive coupling, disassemble.
10) Remove the flexible mount nut, lift the engine, and remove it from the engine base.
(Leave the flexible mount attached to the engine base.)
• Disassembling an engine in a workshop
(1) Drain cooling water
Refer to 2.2.5(6).
1) Open a seawater drain cock to drain the seawater.
2) Open a drain cock on the cylinder body to drain the fresh water from the cylinder head and cylinder
body.
3) Open a fresh water drain cock on the lower part of the coolant tank to drain the fresh water.
4) Open a fresh water drain cock on the lower part of the fresh water pump to drain the fresh water.
Fresh water
pump
Seawater pump
Drain cock for seawater
(2) Drain lube oil
1) Remove the pipe coupling bolt, which holds the lube oil dipstick guide, and drain the lube oil from
the engine.
2) Remove the drain plug on the lower part of the crank case control side, and drain the lube oil from
the marine gearbox.
Coolant tank
Drain cock for coolant
77
Drain cock for seawater