Evinrude 4906B 4HP 1969, Руководство пользователя

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2-10 TUNING
Two
of
the many types
of
fuel purr
IS
installed on
OMC outboard engines. These fuel
pu IpS
cannot be
rebuilt, as explained in the text.
to enter the crankcase and w t foul the
spark plug at idle-speed. Durin high-speed
operation, gas quantity is Emit d, the plug
is not foul and will therefor fire in a
satisfactory manner.
If the fuel pump falls to per orm proper-
ly, an insufficient fuel supply will be de-
livered to the carburetor. This lack of fuel
will cause the engine to run If .an, lose rpm
or cause piston scoring.
When a fuel pressure gauge is added to
the system, it should be installed at the end
of the fuel Iine leading to the upper carbu-
retor. To ensure maximum performance,
the fuel pressure must be 2 psi or more at
full throttle.
This fuel pump is the only OMC pump that can
be
rebuilt. Replacement parts are available from the local
OMC dealer.
Tune-up Task
Most fuel pumps are equipped with a fuel
filter. The filter may be cleaned by first
removing the cap, then the filter element,
cleaning the parts and drying them with
compressed air, and finally installing them
in their original position.
A fuel pump pressure test should be
made any time the engine falls to perform
satisfactorily at high speed.
NEVER use liquid Neoprene on fuel line
fittings. Always use Permatex when making
fuel line connections. Permatex is available
at almost all marine and hardware stores.
Only one Johnson/Evinrude fuel pump
may be rebuilt, see accompanying illustra-
tion. All others pumps must be replace as a
unit. For fuel pump service, see Chapter 4.
2-10 STARTER AND SOLENOID
Starter Motor Test
Check to be sure the battery has a 70-
ampere rating and is fully charged. Would
you believe, many starter motors are need-
lessly disassembled, when the battery is
actually the culprit.
Lubricate the pinion gear and screw
shaft with No. 10 oil.
Connect one lead of a voltmeter to the
posi
t
ive terminal of the starter motor.
Commercial additives, such as Sui-btl, may be used
to
keep the gasoline in the fuel tank fresh. Under
favorable conditions, such additives will prevent the
fuelfrom "souring" for up to twelve months.