MerCruiser 305 CID (5.0L) Service Manual page 725

SEAWATER COOLED MODELS
Seacock (Seawater Inlet Valve)
If a seacock is being used, it must be installed between water pickup and seawater pickup
pump (or sea strainer), to allow operator to shut off the seawater in case of a leak or when
boat is not in use. This will allow the operator to flush or drain the engine, or clean the sea
strainer while boat is in the water. Seacock used must have an internal cross-sectional area
equal to or greater than hose to prevent restricting water flow. Install seacock in an area
where it will be easily accessible and self-supporting to prevent hose fatigue.
Seacock (with Thru-Hull Pickup Shown)
Sea Strainer
If boat is equipped with a sea strainer, it must be of sufficient size to ensure that an adequate
supply of water is maintained for engine cooling. Install seawater strainer in an area where
it will be easily accessible for inspection and cleaning. Strainer should be installed in water
inlet hose after water inlet valve to allow operator to shut off water when cleaning strainer.
Index
Page 6A-4
a - Hose Connector 1-1/4 in. (32 mm) I.D. To Seawater Pump Inlet
b - Seacock 1-1/4 in. (32 mm) Brass Ball Or Gate Valve
c - Seawater Pickup
d - Direction Of Seawater Flow
a
b
c
SERVICE MANUAL NUMBER 24
d
90-861327--1 OCTOBER 1999
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