Flushing Seawater System; Sterndrive (Mcm) Models - Mercury MerCruiser D2.8L D-Tronic Service Manual

SERVICE MANUAL NUMBER 22

Flushing Seawater System

If engine is operated in salty, polluted or mineral-laden water, flush seawater section of
cooling system (preferably after each use) to reduce corrosion and prevent the
accumulation of deposits in the system. Thoroughly flush seawater section prior to storage.

SternDrive (MCM) Models

When flushing, be certain the area around propeller is clear and no one is standing
nearby. To avoid possible injury, remove propeller.
1. Install Flushing Attachment (or equivalent) over water pickup openings in gear housing.
2. Attach a hose between the flushing attachment and a water source.
3. Lower sterndrive unit to full DOWN/IN position.
Do NOT run engine above 1500 rpm when flushing. Suction created by seawater
pickup pump may collapse flushing hose, causing engine to overheat.
4. Partially open water tap (approximately 1/2 maximum capacity). DO NOT use full water
pressure.
5. Place remote control in NEUTRAL, IDLE speed position and start engine.
6. Operate engine at IDLE speed in NEUTRAL for 10 minutes, then stop engine.
7. Shut off water tap.
8. If boat is in the water, raise sterndrive unit to TRAILER position.
9. Remove hose and flushing attachment.
90-860074--1 FEBRUARY 2002
a - Flushing Attachment
b - Hose
WARNING
a
b
CAUTION
MAINTENANCE
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