Mercury 15 TwoStroke, Operation, Maintenance & Installation Manual

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Flushing the Cooling System
Flush the internal water passages of the outboard with fresh water after each
use in salt, polluted, or muddy water. This will help prevent a buildup of
deposits from clogging the internal water passages.
Use a Mercury Precision or Quicksilver accessory (or equivalent) flushing
attachment.
IMPORTANT: The engine must be run during flushing in order to open the
thermostat and circulate water through the water passages.
!
WARNING
Rotating propellers can cause serious injury or death. Never operate the boat
out of the water with a propeller installed. Before installing or removing a
propeller, place the drive unit in neutral and engage the lanyard stop switch
to prevent the engine from starting. Place a block of wood between the
propeller blade and the anti‑ventilation plate.
1. Remove the propeller. Refer to
Propeller Replacement
. Install the
flushing attachment so the rubber cups fit tightly over the cooling water
intake.
27256
Flushing Device 91‑44357Q 2
9192
Attaches to the water intakes; provides
a fresh water connection when flushing
the cooling system or operating the
engine.
MAINTENANCE
56
eng