Cleaning Quicksilver Seawater Strainer; Flushing Seawater Cooling System - Mercury D4.2L Manual

CE376

Cleaning Quicksilver Seawater Strainer

NOTE: Refer to manufacturers instructions if equipped with other than a Quicksilver seawater strainer.
When cleaning seawater strainer, close seacock, if so equipped. If boat is not equipped with a seacock,
remove and plug seawater inlet hose to prevent a siphoning action that may occur, allowing seawater
to flow from the drain holes or removed hoses.
1
With engine off, close seacock if so equipped, or remove and plug seawater inlet hose. Remove screws and
washers, and cover. Remove strainer, drain plug and washer, and clean any debris from strainer housing; flush
both strainer and housing with clean water. Check gasket - replace when necessary (if it leaks). Reinstall drain
plug and washer. Reattach cover with screws and washers. Prior to starting engine, open seacock if so equipped,
or remove plug from seawater inlet hose and reconnect. Tighten hose clamps securely. After starting engine,
check for leaks, and/or air in system (which would indicate an external leak).
A
Screws and Washers
B
Cover
C
Strainer
D
Drain Plug and Washer
E
Housing
F
Gasket
CD172

Flushing Seawater Cooling System

To prevent silt and/or salt buildup in the seawater circuit of cooling system, flush with tap water at specified
Intervals.
When flushing, be certain the area around propeller is clear, and no one is standing nearby. To avoid
possible injury, remove propeller.
Do not run engine above 1500 RPM when flushing. Suction created by seawater pickup pump may
collapse flushing hose, causing engine to overheat.
Watch temperature gauge on dash to ensure that engine does not overheat.
2
Install Quicksilver flushing attachment (G) (or equivalent) over water intake openings in gear housing.
NOTE: If flushing cooling system with boat in water, raise drive unit to TRAILER position, install flushing attach-
ment and lower drive unit to full down/in position.
3
Connect hose (H) between flushing attachment and water tap.
4
With drive unit in normal operating position, partially open water tap (about 1/2 maximum). Place remote con-
trol in NEUTRAL, idle speed position and start engine. Operate engine at idle speed, in NEUTRAL, for about
10 minutes, or until discharge water is clear. Stop engine, shut off water and remove flushing attachment.
5
The closed section of cooling system that contains coolant does not need to be flushed. Coolant is changed
at specified intervals. Refer to "Maintenance Schedule."
CAUTION
WARNING
CAUTION
CAUTION
85