Yanmar 6LY3 series Service Manual page 56

PERIODIC MAINTENANCE
Check or Replace the Flexible Engine
Mounts
The flexible engine mounts compress at initial
engine operation. This may cause misalignment of
the engine and propeller shaft. Check for cracks on
the rubber engine mounts. Replace the engine
mount(s) if damage or misalignment is found.
Replace the Engine Coolant
Be sure to replace the coolant every year. When
the LLC is used, a replacement period of 2 years
can be obtained.
Use clean soft water and add the LLC to the water
in order to prevent rust buildup and freezing.
Cooling capacity drops when coolant is
contaminated with rust and scale.
Even if antifreeze or antirust is added, the coolant
must be replaced periodically because it naturally
degenerates.
1. Place an approved container under the drain
cocks.
2. Open the two coolant drain cocks
(Figure 4-28) and completely drain all the
coolant from the system.
Figure 4-28
(2)
Figure 4-28
1 – Seawater Drain Cock
2 – Coolant Drain Cock
4-24
(1)
0006187
© 2007 Yanmar Marine International
Periodic Maintenance Procedures
Figure 4-29
(1)
(5)
Figure 4-29
1 – Freshwater Pump
2 – Coolant Tank
3 – Seawater Drain Cock
4 – Coolant Drain Cock
5 – Seawater Pump
3. Close the two coolant drain cocks. Be sure to
check that the two seawater drain cocks are
closed.
4. Remove the coolant filler cap (Figure 4-30, (1))
on the coolant tank (Figure 4-30, (3)) by turning
the cap counterclockwise 1/3 of a turn.
Figure 4-30
(1)
(2)
(4)
Figure 4-30
1 – Filler Cap
2 – Tabs
3 – Coolant Tank
4 – Notches
5. Pour coolant slowly into the coolant tank so that
air bubbles do not develop. Pour until the
coolant overflows from the filler port.
6LY3 Service Manual
(2)
(3)
(4)
0006188
(3)
0006189