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1967 Johnson 9.5hp adjustment?

Re: 1967 Johnson 9 1/2 adjustment?

LOW - SPEED NEEDLE ADJUSTMENT
(1971 JOHNSON 9.5 HP SERVICE MANUAL)
a. Turn needle valve clockwise until it closes and seats. DO NOT force needle against seat, as the taper on the needle may be damaged.
b. Turn needle valve counterclockwise 3/4 turn.
c. Start motor
NOTE:
Allow motor to reach normal operating temperature by running in a tank with test propeller at one-half throttle or slightly more for at least 5 minutes before proceeding to the next step.
d. With motor in gear, run at full throttle briefly to clear motor out. Keep engine in gear and retard throttle to idle position (700-750 rpm) and slowly lean low-speed needle valve by turning clockwise until motor hesitates or spits slightly; then enrich setting by turning counterclockwise to where the motor runs the fastest and the smoothest. Allow 15 seconds for the motor to respond to adjustment.
e. Replace low-speed adjusting knob set midway between lean and rich. Be careful not to disturb position of needle while installing adjusting knob.
f. Adjust idle adjustment knob so motor will idle at 550 rpm IN GEAR.
 
Re: 1967 Johnson 9 1/2 adjustment?

Normally once the mixture screw has been correctly sett ( See HERE for Joe Reeves' detailed instructions ) the knob should be simply left in its mid position. If necessary to tweek the idle mixture at all you can do so with this knob.
( I find it useful to make the mixture a little richer than normal briefly while the motor is warming up after a cold start.)
 
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