Fuel System
The 239DFS is equipped with a single, 100 Gallon, pressurized fuel tank. The tank is of aluminum construction and is secured/insulated with foam
during the construction of the boat. The tank is located on centerline between the livewell and aft end of the Fishbox/Ski Locker. There is a
sending unit installed in the tank. Inspection ports in the deck and head compartment provide access to tank fittings.
There is a fuel pickup installed in the tank. The pickup incorporates a shut off valve along with an anti‐siphon valve than can be accessed through
the in deck inspection plate, adjacent to the convenience center.
There is an on deck fuel fill located on the port side of the boat, outboard of the windshield and adjacent to the passenger console door. The tank
vents through an EPA Carbon Canister, located in the anchor locker, which than vents overboard through a vent fitting on the starboard side of the
hull. Access to the vent is provided through an inspection port. It is recommended that these connections be inspected annually.
The 239DFS will come pre‐rigged from the factory with an engine matched Fuel Water Separator. The fuel water separator is installed in the bilge
and accessed through the bilge access hatch located in the engine pod. The Fuel Water separator should be checked periodically to ensure the fuel
is free of water. Fuel should be disposed of in an approved waste collection device when servicing/replacing. The filter must be filled with fuel
after servicing/replacing them in order to prime the engine.
A primer bulb for the engine is located in the engine pod. It is used to prime the engine and system before starting the engine. This should be done
after service or after periods of downtime for the boat.
When refueling the 239DFS, whether on trailer or at a marina, the pressurized system will prevent overfilling. Any blockage of the vent, vent line
and/or orifice line will prematurely trigger the shut off on the fuel nozzle and will prevent you from filling the tank completely. It is recommended
to inspect your fuel system annually to ensure that all hose fittings are secured and the lines are free of any kinks. All components of the 239DFS
Fuel System are approved for use with ethanol blended fuels up to 10%. E85 fuel should never be used. Key West recommends using non ethanol
fuels whenever possible to reduce the risk of moisture retention in the fuel system, especially in areas of high heat/humidity.
Due to the emission requirements of the EPA, certified fuel tanks and systems will not fill to the top of the tank. Instead, there will be a ullage in
the top 10% of the tank. The specified capacity of the tank (100 Gallons) accounts for this ullage when the tank is static and level. Therefore, it is
important to make sure the boat is as level as possible when filling the tank. Any forward or aft tilt will cause fuel to collect in one end of the tank
and prematurely reach either the forward or aft tank vent. When fuel reaches these vents, it triggers the shut off. When the boat is level, fuel will
reach these vents at the same time and allow the maximum quantity of fuel into the tank. The tanks ullage will also affect your fuel gauge as the
tanks sending unit will not reach the top of the tank, even when the tank is filled. This will cause the fuel guage to not read full, even though it is.
Do not rely on the fuel gauge exclusively as variations will occur.
The stated capacity of the 239DFS tank
DOES
NOT
reflect the quantity of usable fuel in the tank. The tank and its pickup are designed to allow as
much fuel to be used as possible when on plane or in the boat’s level floating position, but it will not allow all fuel to be used. When using your
boat, it is a good practice to keep a log and a running count of how much fuel you’ve used.
