Ignition Timing - Suzuki DF150 Service Manual

9. During this fixed mode of IAC valve duty, adjust engine
speed to 650 ± 50 r/min. by turning by-pass air screw.
Turning air screw counterclockwise:
Turning air screw clockwise:
10. When finished adjusting the idle speed, opening the throttle
will automatically cancel the IAC fixed mode.
NOTE:
The fixed mode of IAC can also be canceled manually by shift-
ing to Forward or Reverse or raising the engine speed (changes
the TPS full close throttle signal to OFF).
11. Return the throttle to full close and check engine speed. It
should now be stable at 600 – 700 r/min.
NOTE:
Idling/trolling speed of 600 – 700 r/min. is controlled by IAC (idle
air control) system.
If engine speed does not return to specification, IAC passage
may be clogged or IAC system may not be operating correctly.
See "IDLE AIR CONTROL SYSTEM" section on page 3-26.
NOTE:
Trolling speed (in-gear idle speed) is same as idle speed.

IGNITION TIMING

Inspect every 200 hours (12 months).
NOTE:
Before checking the ignition timing, make sure idle speed is
adjusted within specification.
1. Start the engine and allow to warm up.
2. Attach the timing light cord to the No. 1 ignition coil primary
wire.
! 09930-76420: Timing light
3. Check the ignition timing while operating the engine in neu-
tral gear at 1 000 r/min.
Ignition timing: Approx. BTDC 10° at 1 000 r/min.
Engine speed will increase.
Engine speed will decrease.
PERIODIC MAINTENANCE
2
1. Throttle body
2. By-pass air screw
1
1. No.1 ignition coil
2-17
1