2-14 PERIODIC MAINTENANCE
IDLE SPEED
Inspect initially after 20 hours (1 month) and every 200
hours (12 months).
NOTE:
•
Before checking idle speed, engine should be allowed to warm
up.
•
Check and/or adjust idle speed after engine speed has sta-
bilized.
•
Before checking idle speed, check throttle link mechanism
and throttle valve for smooth operation.
1. Start engine and allow to warm up.
2. Attach engine tachometer to the ignition high-tension cord.
\ 09900-26006 : Engine tachometer
3. Check engine speed.
Idle speed (in neutral gear) : 600 – 650 r/min.
ADJUSTMENT :
If idle speed is out of specification, perform following adjust-
ment procedure.
4. Check that CTP switch is in ON position.
5. To set the IAC valve duty to constant 15%, raise engine
speed to 1000 r/min. or higher by turning the by-pass air
screw and hold that speed for 10 seconds.
At this time, caution buzzer will sound to notify that IAC duty
is in fixed mode.
Turning air screw counterclockwise :
Engine speed will increase.
Turning air screw clockwise :
Engine speed will decrease.
NOTE:
•
While IAC valve duty is at fixed 15%, caution buzzer will sound
for repeated 0.5 second with an interval of 3 seconds.
•
The 15% fixed mode of IAC valve duty will continue for 5
minutes and then it will be automatically cancelled.
6. During fixed mode of IAC valve duty, adjust engine speed
to 625 ± 25 r/min. by turning by-pass air screw.