Through-Hull Seawater Pickup System; Seawater Pickup - Mercury MerCruiser Product Applications Manual

Through-Hull Seawater Pickup System

IMPORTANT: Seawater hose used must be wire reinforced to avoid collapsing hose when
suction is created by seawater pump impeller.
f
Typical installation shown with a through the hull seawater pickup
IMPORTANT: Do not install the seawater pickup directly in line with the propeller, as the
pickup may create turbulence and allow air to flow into the propeller slipstream. This will
cause propeller ventilation and will adversely affect boat performance.
IMPORTANT: Make gradual bends in the seawater hoses to avoid kinks. Hoses must not
come in contact with steering system components, engine coupler, or drive shaft.
• The seawater pickup must be large enough to permit sufficient seawater flow to engine
seawater pickup pump for adequate engine cooling.
• The seawater pickup also must supply a positive head while underway.
• The seawater pickup should be located as close to the seawater pump inlet as possible
and in an area where an uninterrupted, solid stream of seawater will flow past when
the boat is underway.

Seawater Pickup

Either a through-transom or through-hull seawater pickup can be used. Select pickup
location to minimize seawater inlet hose length while providing an optimum location for
seawater pickup. The location should be in an area that will provide a solid, air-free flow of
seawater under all operating conditions. Avoid areas with a disturbed seawater flow, such
as those behind or in close proximity to the propeller. Locations that are too far forward or
outboard should also be avoided as these are prone to aeration problems at high boat trim
angles and in turns. Check for aeration as outlined under Seawater Supply Test.
IMPORTANT: Do not install the seawater pickup directly in line with the propeller, as pickup
may create turbulence and allow air to flow into the propeller slip-stream. This will cause
propeller ventilation and will adversely affect boat performance.
90-863758060 AUGUST 2006
b
e
a - Quicksilver seawater pickup and
seacock
b - Hose clamp
c - Seawater hose to seawater
strainer
d - Quicksilver seawater strainer
g
b
b
d
a
e -
f -
g -
Cooling System
c
7924
Seawater hose to engine
Seawater pump hose connector (if
equipped)
Below seawater pump level
Page 7A-5