Fuel Demand Valve (Fdv) Requirement; Mercury Marine's Pressurized Portable Fuel Tank - Mercury 200 OptiMax DTS Manual

• An air inlet that opens to allow air to enter as the fuel is
drawn out of the tank.
• An air outlet that opens (vents) to the atmosphere if
pressure exceeds 34.4 kPa (5.0 psi).

Fuel Demand Valve (FDV) Requirement

Whenever a pressurized fuel tank is used, a fuel demand valve
is required to be installed in the fuel hose between the fuel tank
and primer bulb. The fuel demand valve prevents pressurized
fuel from entering the engine and causing a fuel system overflow
or possible fuel spillage.
The fuel demand valve has a manual release. The manual
release can be used (pushed in) to open (bypass) the valve in
case of a fuel blockage in the valve.
a

Mercury Marine's Pressurized Portable Fuel Tank

Mercury Marine has created a new portable pressurized fuel tank
that meets the preceding EPA requirements. These fuel tanks
are available as an accessory or are provided with certain
portable outboard models.
SPECIAL FEATURES OF THE PORTABLE FUEL TANK
• The fuel tank has a two‑way valve which allows air to enter
the tank as the fuel is drawn to the engine, and also opens
to vent to the atmosphere if internal pressure in the tank
exceeds 34.4 kPa (5.0 psi). A hissing noise may be heard
as the tank vents to the atmosphere. This is normal.
• The fuel tank includes a fuel demand valve that prevents
pressurized fuel from entering the engine and causing a fuel
system overflow or possible fuel spillage.
eng
FUEL AND OIL
b
a -
b -
c
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c -
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Fuel demand valve ‑ installed
in the fuel hose between the
fuel tank and primer bulb
Manual release
Vent/water drain holes