Evinrude 4906B 4HP 1969 Owner's Manual page 99

4-8 FUEL
A typical squeeze bulb with the directional
clearly visible. The squueze bulb must
the arrow pointing in the direction
the engine.
should be carried on board for use in isolat-
ed areas where a marine store is not avail-
able. For a small additional
entire fuel line can be replaced and elimi-
nate this entire area as a problem source for
many future seasons.
The primer squeeze bulb can be replaced
in a short time. A squeeze bulb assembly,
complete with the
may be obtained from the local OMC dealer.
An arrow is clearly
squeeze bulb to indicate
fuel flow. The squeeze bulb MUST be instal-
led correctly in the line because the check
valves in each end of the bulb will allow fuel
to flow in ONLY one direction.
if the squeeze bulb should be installed back-
wards, in a moment of haste to get the job
done, fuel will not reach the carburetor.
To replace the bulb, first
clamps on the hose at each end of the bulb.
Next, pull the hose out of the check valves
at each end of the bulb.
included with a new squeeze bulb.
If the fuel line has been exposed
considerable sunlight, it may have become
hardened, causing difficulty
over the check valve.
Obsolete pressure-type
on
operated primer pump
to
pump fuel the engine.
pressure forces fuel from the tank
arrow
be installed
of
fuel flow, toward
expense, the
check valves installed,
visible on the
the direction
Therefore,
unsnap the
New clamps are
in working it
To remedy this
fuel tank. A manually-
the fuel tank is worked
After engine start,
to
the engine.
situation, simply immerse the ends of the
hose in boiling water for a few minutes to
soften the rubber. The hose will then slip
onto the check valve without further
lems. After the lines on both sides have
been installed,
secure the line. Check a second time to be
sure the arrow is pointing in the fuel flow
with
direction, TOWARDS the engine.
TESTING SYSTEM WITH PRESSURE TANK
Some early model small engines produc-
ed by OMC used a type of fuel system
utilizing two hoses connected to the engine.
To prime this system, a primer pump on the
fuel tank, is worked to manually pump fuel
to the engine.
pressurize the tank, all that is accomplished
is to deliver fuel to the carburetor.
the engine starts, air is pumped through the
second hose and the fuel tank is pressurized
of
to maintain
carburetor.
MUST be securely in place for this system to
function properly.
A release valve installed in the fuel tank
will automatically
should build above a predetermined
ing.
A fuel pump may be installed
engine equipped with this type of pressure
system. Replacement
tanks has become quite expensive,
fore, the fuel pump option may be worth
to
considering instead of replacing the pressure
tank.
To install a fuel pump it is first neces-
sary to remove
plate alongside the upper or lower cylinder.
to
air
snap the camps in place to
Working this pump does
a steady fuel supply to the
The filler cap on the fuel tank
release air if the pressure
of these
the intake bypass cover
prob-
NOT
Once
psi rat-
on any
pressure
there-
AIR
PRESSURE
/
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