Kohler COMMAND CH18, Руководство по обслуживанию

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5.12
Section 5
Fuel System and Governor
Lean
Rich
Adjust to
Midpoint
Lean
Rich
Adjust to
Midpoint
Left Side Right Side
*NOTE: Engines operating at altitudes above
approximately 1500 m (5000 ft.) may require
a special ‘‘high altitude’’ main jet. Refer to
‘‘High Altitude Operation.’’
If, however, the engine is hard-starting or does not
operate properly, it may be necessary to adjust or
service the carburetor.
2. Place the throttle control into the “ idle ” or
“ slow ” position. Adjust the low idle speed to
1200 RPM* . Follow the “Adjusting the Low Idle
Speed (RPM)” procedure.
3. Low Idle Fuel Needle(s) Setting: Place the
throttle into the “idle” or “slow” position.
a. Turn one of the low idle fuel adjusting needles
out (counterclockwise) from the preliminary
setting until the engine speed decreases (rich).
Note the position of the needle. Now turn the
adjusting needle in (clockwise). The engine
speed may increase, then it will decrease as
the needle is turned in (lean). Note the
position of the needle. Set the adjusting
needle midway between the rich and lean
settings. See Figure 5-13.
b. Repeat the procedure on the other low idle
adjustment needle.
4. Recheck/adjust the Low Idle Speed (RPM) , to the
specified setting.
Figure 5-13. Optimum Low Idle Fuel Settings.
Models with Governed Idle System
An optional governed idle control system is supplied
on some engines. The purpose of this system is to
maintain a desired idle speed regardless of ambient
conditions (temperature, parasitic load, etc.) that may
change. Engines with this feature contain a small
secondary spring connected between the governor
lever and the lower adjustment tab of the main
bracket. See Figure 5-14.
The system requires an additional procedure for
setting the idle speed. If speed adjustments are
required proceed as follows.
Low Idle Fuel Adjustments
(With Limiters)
Low Idle Speed
(RPM) Adjustment
Screw
Fuel Solenoid
Figure 5-12. Keihin Two-Barrel Carburetor.
Carburetor Adjustment
Low Idle Speed (RPM) Adjustment
1. Low Idle Speed (RPM) Setting: Place the throttle
control into the “ idle ” or “ slow ” position. Set the
low idle speed to 1200 RPM* (± 75 RPM) by
turning the low idle speed adjusting screw in or
out . Check the speed using a tachometer.
*NOTE: The actual low idle speed depends on the
application. Refer to the equipment
manufacturer’s recommendations. The low
idle speed for basic engines is 1200 RPM. To
ensure best results when setting the low idle
fuel needle, the low idle speed should be
1200 RPM (± 75 RPM).
Low Idle Fuel Adjustment
NOTE: Engines will have fixed low idle or limiter
caps on the two idle fuel adjusting needles.
Step 3 can only be performed within the
limits allowed by the cap. Do not attempt to
remove the limiter caps.
1. Start the engine and run at half throttle for 5 to
10 minutes to warm up. The engine must be
warm before doing steps 2, 3, and 4.