CORRECT CRAFT Nautique 220 Owner's Manual page 180

The raw water strainer bowl (A) remains full of water even after the
rest of the engine cooling water system is drained. To properly
winterize your boat, the strainer bowl must be removed and
emptied. DO NOT lose the rubber O-ring (B) that seals the bowl to
the cap. Clean screen (C) if required. If the water is not removed,
the bowl can be damaged. A damaged strainer can cause
overheating problems during the next season.
RAW WATER
STRAINER
OFF
ON
WATER
VALVE
A
Storage
CORC067
C
B
CORC078
10-3