SELVA MARINE Blue Whale 250 EFI, Service Manual

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GEN
INFO
General information
1-27
6P23H11
Knock control system
In the Blue Wlale 250 engine, the knock sensor detects the engine knock that occurs due to abnormal
combustion during operation and determines whether there is engine knock and its size. When
engine knock is determined, the knock control system retards the ignition timing to prevent the
occurrence of engine knock.
Knock control
Description Control Engine condition
Knock Detects whether engine knock occurs at
ignition. When engine knock is detected, the
ignition timing is retarded by a fixed amount. When the engine speed is
higher than the engine idle
speed after warming the
engine up.