MerCruiser GM4 Service Manual page 28

! WARNING
When flushing cooling system with boat out of
the water, be certain that area in vicinity of propel-
ler is clear and that no person is standing nearby.
As a precautionary measure, it is recommended
that propeller be removed.
! CAUTION
To prevent engine or stern drive unit damage DO
NOT run engine or drive unit without water being
supplied to water intake openings on gear hous-
ing, and to seawater pickup pump if so equipped.
1. Connect flushing attachment as follows:
NOTE: If flushing cooling system with boat in water,
raise drive unit to trailer position and install flushing
attachment. Lower drive unit to full IN/DOWN posi-
tion.
a. Install Quicksilver Flushing Attachment (or
equivalent) over water intake openings in
gear housing.
b. Connect hose between flushing attachment
and water tap.
a
a - Quicksilver Flushing Attachment
b - Garden Hose
Index
1B - 12 - MAINTENANCE
If cooling system is to be flushed with boat in the
water, seacock (if so equipped) must be closed,
or water inlet hose must be disconnected and
plugged to prevent water from flowing into boat.
2. Partially open water tap(s) (approximately 1/2
maximum capacity) and allow drive unit and cool-
ing system to fill completely. Do not use full tap
water pressure.
a - Quicksilver Flushing Attachment
b - Water To Drive Unit
NOTE: Drive unit is full when water is discharged out
of drive unit, and/or seawater section of closed cooled
system is full when water is discharged through pro-
peller.
b
Do not run engine above 1500 RPM when flush-
ing. Suction created by seawater pickup pump
72012
may collapse flushing hose, causing engine to
overheat.
3. Place remote control lever in NEUTRAL position
and start the engine.
! CAUTION
a
b
! CAUTION
90-816462 2-695
72672