Evinrude 4906B 4HP 1969, Руководство пользователя

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Start the engine and allow it to warm to
operating temperature.
CAUTION: Water must circulate through
the lower unit to the engine any time the en-
gine is run to
prevent damage to the water
pump in the lower unit. Just five seconds
without water will damage the water pump.
NEVER, AGAIN NEVER, operate the en-
gine at high speed with a flush device at-
tached. The engine, operating at high speed
with such a device attached, would RUN-A-
WAY from lack of a load on the propeller,
causing extensive damage.
With t he engine running in forward gear,
slow ly turn the idle mixture screw COUN-
TERCLOCKWISE until the affected cylin-
ders start to load up or fire unevenly, due to
an over-rich mixture. Slowly turn the idle
mixture screw CLOCKWISE until the cylin-
ders fire evenly and engine rpm increases.
Continue to slowly turn the screw CLOCK-
WISE until too lean a mixture is obtained
and the rpms fall off and the engine begins
to misfire. Now, set the idle mixture screw
one-quarter 0/4) turn out <Counterclock-
wise) from the lean-out position. This ad-
justment will result in an approximate true
setting. A too-lean setting is a major cause
of hard starting a cold engine. It is better
to have the adjustment on the rich side
rather than on the lean side. Stating it
another way, do not make the adjustment
A 3.0 hp engine with the low- and high-speed adjust-
m
ents clearly visible.
FUEL PUMP 2-9
an y leaner than necessary to obtain a smooth
idle.
If the engine hesitates during acceleration
after adjusting the idle mixture, the mixture is
too lean.
Enrich the mixture slightly, by turn-
ing the adjustment screw outward until the
engine accelerates correctly.
With the engine running in forward gear,
rotate the nylon idle adjustment screw, located
on the portside of the powerhead until the
powerhead idles at the recommended rpm.
This idle adjustment screw is always exposed on
the outside of the shroud.
Repairs and Adjustments
For detailed procedures to disassemble,
clean, assemble, and adjust the carburetor,
see the appropriate section in Chapter 4 for
the carburetor type on the engine being
serviced.
2-9 FUEL PUMPS
Many times a
defective
fuel pump dia-
phragm is mistakenly diagnosed as a prob-
lem in the ignition system. The most com-
mon problem is a tiny pin-hole in the dia-
phragm. Such a small hole will permit gas
A larger hp engine with the idle return stop screw
indicated. This stop screw is adjustable and prevents
the throttle from returning so far as to shut down the
engine.