Yanmar 4BY, Service Manual, Page: 169 / 275

COOLING SYSTEM
7-10
BY Service Manual
Repair
REPAIR
Prepare Engine for Long-Term
Storage
IMPORTANT
Do not drain engine coolant for long-term
storage.
Antifreeze must be used to avoid freezing
and damaging of components. Antifreeze
will prevent rusting during long-term
storage.
1. Change engine oil and filter.
2. Drain seawater cooling system. See Drain
Seawater Cooling System on page 7-10.
3. Wipe off any dust or oil from the outside of
engine.
4. Drain fuel tank or fill the tank to prevent
condensation.
5. Grease the exposed areas and joints of the
remote control cables and the bearings of the
remote control handle.
6. Seal the intake silencer, exhaust pipe, etc. to
prevent moisture or contamination from
entering engine.
7. Completely drain bilge in hull bottom.
8. Waterproof the engine room to prevent rain or
seawater from entering.
9. Charge the battery once a month to
compensate for battery’s self-discharge.
10. Remove key from key switch and cover key
switch with moisture cap (if equipped).
Drain Seawater Cooling System
IMPORTANT
If water fails to drain from any open drain
cock or port, remove the cock completely
and probe the opening with a small piece of
wire to loosen debris.
Figure 7-4
1. Open the lower seawater drain cock
(Figure 7-4, (1)) located in the piping between
the seawater pump and hydraulic oil cooler.
Allow to drain.
2. Open the drain cock (Figure 7-4, (2)) on the
bottom of the charge air cooler.
3. Loosen the seawater pump cover
(Figure 7-4, (3)) to allow water to drain. See
Seawater Pump on page 7-20.
IMPORTANT
Be sure O-ring is in place in groove of
housing.
4. When water has drained, install cover and
tighten bolts.
5. Remove zinc anodes from the engine heat
exchanger (Figure 7-4, (4)) and intake air
cooler (Figure 7-4, (5)) and allow water to drain
from housings.
000 3 659
(1)
( 3 )
(2)
(4)
(5 )