Regal LS4C Owner's Manual page 68

Fuel Vent Fitting - Typical
Currently, domestic EPA
compliant fuel tanks vent
fumes through the fuel tank
system. While the tank
is being filled fuel vapors
displaced by the incoming
fuel are vented through the
FUEL FILL FITTING
fuel system charcoal canister and low perm hoses
eventually to and through the hull side fuel vent.
This purging process occurs on a continuous
basics as the fuel in the tank expands due to both
internal and external temperature changes. On
these systems periodically check the fuel vent
screen for debris and obstructions such as insect
nests.
Select fuel systems may use a combo type (internal
vented) fuel fill. Both the fuel fill and vent occupy
the same cavity under a protective cover. If fuel
overflows through the vent it is forced back into
the fuel fill hose and tank.
On all systems be sure to tighten the fuel fill cap
to prevent water and debris from entering the fill
system. On select systems you may hear a distinct
sound as the tank nears the "top out" or full mode.
NOTICE
DO NOT OVERFILL THE FUEL TANK!
THIS HELPS AVOID ANY OVERBOARD
SPILLS WHICH MAY HARM THE
ENVIRONMENT.
Anti-Siphon Valve
INTERNAL BALL/SPRING
The valve is threaded into the fuel tank fitting at
the feed line. The valve is pulled off its seat by
fuel pump pressure as the engine is cranking or
running. There is a ball and spring assembly inside
the valve that is activated by fuel pump impulses.
It allows a one-way fuel roadway to the engine
or generator fuel system. It prevents fuel from
siphoning out of the tank in the event of a fuel
line rupture or damaged fuel feed hose. When the
engine fuel components stop the fuel from cycling
the spring forces the ball against the valve opening
to prohibit fuel flow.
Never remove an anti-siphon valve as it is a fuel
system safety component. Also, never remove
the ball and spring from the valve assembly. The
anti-siphon valve requires no normal maintenance.
Symptoms indicating possible valve problems may
be fuel starvation at intermediate or high rpm or in
extreme cases an engine that will not start.
Contact your Regal dealer for further information.
The gasoline fuel
tank feed line that
runs from the fuel
tank to an engine
fuel component uses
an anti-siphon valve.
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