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TECH FEA

Technical features and description

Basic ignition timing The basic ignition timing is divided into 3 types: engine starting ignition timing, idling basic ignition timing, and normal basic ignition timing. Basic ignition timing Engine starting ignition timing (BTDC 10°) Idling basic ignition timing Normal basic ignition timing

Criteria Engine is starting (less than 500 r/min) Engine speed is at engine idle speed Engine speed is more than engine idle speed

Ignition cylinder All cylinders simultaneously Each cylinder sequentially Each cylinder sequentially

Ignition timing restriction The advancing or retarding of the ignition timing is restricted according to the engine speed, engine temperature, and dashpot function. Restriction Engine speed restriction

Corresponding sensor Pulser coil

Engine temperature restriction

Engine temperature sensor

Dashpot function restriction (when the throttle valve is closed quickly)

Pulser coil and LPS

Details The ignition timing is restricted between BTDC 50° (advance angle) and ATDC 20° (retard angle) according to the engine speed. The ignition timing is restricted between BTDC 50° (advance angle) and ATDC 30° (retard angle) according to the engine temperature. The ignition timing is restricted to ATDC 20° when the dashpot function operates.

Ignition timing compensation The ignition timing control makes advance or retard compensations to the ignition timing according to the engine operating conditions. The compensations are determined according to the signals from the following sensors. Compensation After start-up For stable idle speed During dashpot function operation For shift-cutout control During acceleration

2-9

Corresponding sensor Engine temperature sensor LPS and pulser coil LPS, SPS, and pulser coil Pulser coil and SPS Air pressure sensor and TPS

2011 YAMAHA F225CA 4-STROKE OUTBOARD Service Repair Manual SN:1000001 and up  
2011 YAMAHA F225CA 4-STROKE OUTBOARD Service Repair Manual SN:1000001 and up  
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