Inspection of Ignition Timing Control System

Fig. 13 Ignition timing control terminal:

1. If altitude is lower than 3900 ft. above sea level, check ignition timing with battery voltage applied to ignition timing adjusting terminal and when battery voltage is not applied, Fig. 13. With battery voltage applied, ignition timing at idle should indicate 10° BTDC. With battery voltage applied, timing should be 5° advanced or 15° BTDC.
2. If altitude is higher than 3900 ft. above sea level, check ignition timing when adjusting terminal is grounded, then recheck when terminal is not grounded. When not grounded, ignition timing should be 15° BTDC at idle and when grounded, ignition timing should be retarded by 5° at 10° BTDC.
3. If timing is not as specified, replace ESC igniter.