MAINTENANCE
9. Adjusting high speed:
C
C
C
C
Adjust the low adjustment screw (Ref. L) for the
smooth engine idling. Then increase the engine
speed and adjust the high speed adjustment screw
(Ref.
H)
for stable engine rotation. The engine
acceleration should be smooth with proper
adjustment.
(High Engine Speed ............ 7,500-8,000 min-1)
The standards for the screw turns (from fully closed
positions) are:
Low speed adjustment screw: 1
High speed adjustment screw: 1
The allowance for screw adjustment is ±1/4 turn.
B. CHECKING THE SPARK PLUG.
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0.020" -0.024"
The wrong fuel mix (too much engine oil in the
gasoline), a dirty air filter or unfavorable running
conditions (mostly at low throttle) affect the
condition of the spark plug. These factors cause
deposits to form on the insulator nose which may
result in faulty operation.
14
1. If the engine doesn't seem to have any power, is
difficult to start or runs poorly at idling speed,
first check the spark plug.
2. Remove the spark plug and see "3. If the
Engine Does not Start" on page
14.
3.
Clean the dirty spark plug.
4. Check the electrode gap.
It should be 0.20in.(0.5mm) - 0.024in.(0.6mm)
Re-gap if necessary.
5. Use only a suppressed spark plug of the
approved type:
NGK BPMR7A, ND W22MPR-U
Correct the problems which caused the fouling
of the spark plug:
Incorrect carburetor setting, too much oil in the
fuel mix, dirty air filter, unfavorable running
conditions, e.g. operating at partial load.
C. CLEANING THE AIR FILTER.
Dirty air filters reduce engine power, increase fuel
consumption and make starting more difficult.
If there is a noticeable loss of engine power:
3
2
1. Turn the choke lever (Ref. 1) to
"CLOSE".
Loosen the screw (Ref. 2) and remove the air
filter cover (Ref. 3).
2. Remove the foam element (Ref 4).
3. Wash the felt element in warm, soapy water and
then dry.