Flushing The Cooling System (Powerhead) - Mercury 300 XS OptiMax Manual

EVERY 200 HOURS OR ONCE EVERY TWO YEARS, WHICHEVER
OCCURS FIRST
• Replace the water separating fuel filter.
• Check the spark plug gap and replace if necessary.
BEFORE PERIODS OF STORAGE
•
Refer to Storage section.

Flushing the Cooling System (Powerhead)

Flush the internal water passages of the engine 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.
a
a - Plug located on fitting
b - Water hose
1. Remove the plug from fitting in the bottom cowl.
2. Attach a water hose to the fitting. Turn on the water and flush for three to
five minutes.
NOTE: The engine can be stopped or operated at idle speed when flushing the
cooling system. Do not flush engine using a water system that exceeds
310 kPa (45 psi).
MAINTENANCE
68
b
2730
eng