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SHURFLO® AQUA KING™ II FRESH WATER PUMPS
PREMIUM 4.0 GPM AND SUPREME 5.0 GPM
MODEL SERIES 4148 & 4158
The NEW SHURFLO AQUA KING™ II delivers smooth and high-powered fl ow.
SHURFLO’s New 4148 and 4158 series fresh water pump design was created with unique over-molded single-piece diaphragm
and internal by-pass, assuring long life and top performance in all plumbing systems. Designed as the next legendary pump to
exceed the expectations of our customers, the 4148 and 4158 series pumps are constructed for high fl ow demand, smooth fl ow
and no rapid cycling. Our quality reputation has been built on the reliability and dependability of every pump we build. The 4148
and 4158 series fresh water automatic demand pumps are quiet, thermally protected and can run dry without damage.
FEATURES
❚ 4 independent chambers
❚ Co-Molded diaphragm
❚ Adjustable switch and by-pass
❚ Self-priming up to 6 feet
❚ Dry run capability
❚ Sealed switch
❚ Sealed motor
❚ Corrosion resistant electro coated
motor
❚ Thermally protected
❚ Ignition protected, CE
INSTALLATION TIPS
❚ Properly sized plumbing
❚ Mount on a solid surface within 6 feet
of tank
❚ Properly sized wiring
❚ Use proper fuse size
❚ Install strainer on pump inlet
❚ Dry and accessible location
❚ Minimize plumbing elbows and valves
❚ Flexible high-pressure hose on inlet
and outlet
911-1026 REV. F 1
OPERATION TIPS
❚ Do not adjust switch or bypass settings without contacting customer
service
❚ Pump is designed for intermittent
operation only
❚ Turn off power to the pump when boat
is unattended
❚ Keep your strainer clean for ultimate
pump performance
❚ Do not use pump for Reverse Osmosis
fi ltration system
APPLICATION
❚ Marine 12V DC or 24V DC fresh water
systems—see pump label for rated
voltage
❚ Multi-Fixture, up to 4 fi xtures
❚ General fresh water transfer
❚ Pressurized water systems in cabins
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INSTALLATION
MOUNTING
The goal of installation is to provide a
quiet, easy to maintain installation with
good flow and low back pressure. This
can be accomplished with the following
guidelines:
❚ Mount on a solid surface in an accessible location for strainer cleaning and
pump maintenance.
❚ Use flexible high-pressure hose on
the pump inlet and outlet [such as
SHURFLO Kit 94-591- 01]. The pump
ports and strainer should not be connected to plastic or rigid pipe, or the
pump's normal motion will transmit
through rigid plumbing causing noise,
and possibly loosening or cracking
components.
❚ Pump must use an adequate 50-mesh
strainer [such as SHURFLO 255 series
strainers].
❚ Use a minimum of 1/2" [13mm] Inner
Diameter plumbing. Smaller ID plumbing will cause cavitation, high back
pressure, low flow and noise.
❚ Pump is designed for intermittent duty
only: Do not use these pumps for running a Reverse-Osmosis [RO] Filtration
System. High pressure continuous duty
usage will shorten the life of the pump
and is not covered under warranty.
❚ Wire Size is 14 GA [2.5mm²] MINIMUM, 12GA [4mm²] is recommended—
See Wire Chart in Electrical Section for
minimum sizing.
❚ Minimum power requirement is a 15
Amp circuit.
❚ Reduce restrictions on inlet and outlet. This includes small inner diameter
shut-off valves, winterizing valves and
elbows.
INSTALLATION GUIDELINES
❚ Solid surface within 6 feet of tank
❚ Accessible location
❚ Minimize flow restrictions in the
system
❚ Strainer on pump inlet
❚ Properly sized wiring
❚ Flexible hose on inlet and outlet -
Proper electrical protection
❚ Minimize plumbing elbows and valves
❚ Properly sized plumbing
❚ Mount the pump within 6 feet (Max) of
the tank for best performance and pump
life. The pump will pull farther, but the
farther it pulls the more work it does,
increasing vibration and noise, and
reducing the output and pump life.
❚ Mount pump in a space of at least 1
cubic foot for adequate ventilation to
prevent overheating.
❚ Pump may be mounted in any position.
❚ Mount pump for easy access for
cleaning strainer, maintenance and
service.
❚ Mount pump on a solid surface to
prevent vibration and noise.
ELECTRICAL
❚ The pump should be on a dedicated
(individual) circuit protected by the
specified fuse on the motor label.
❚ A UL marine duty switch (ignition
protected) rated for 15 amps or higher is
recommended, and must interrupt current flow on the positive (+ red) lead.
❚ SHUT OFF POWER TO THE PUMP
WHEN LEAVING THE BOAT UNATTENDED.
Ft. [m] AWG [mm2]
0-20 [0-6] 14 [2.5]
20-50 [6-15] 12 4]
50-70 [15-21] 10 [6]
70-100 [21-30] 8 [8]
Minimum Wire Size for a 10% voltage drop on a 12VDC, 15 Amp
Circuit. Length is the distance from the power source to pump
and back to ground.
PLUMBING
Installation of a strainer is required to
prevent debris from entering the pump.
For noise and vibration reduction we
recommend at least 18 in. [.5 M] of
1/2" [13mm] I.D. flexible high-pressure
hose to both ports. The pump ports and
strainer should not be connected to
Typical Pump Installation
2
plastic or rigid pipe. This hose should
be anchored where it meets the hard
plumbing to reduce plumbing vibration.