See also:

Air cleaner element
Do not operate the engine with the air cleaner element removed. The air cleaner element not only filters intake air but also stops flames if the engine backfires. If the air cleaner elem ...

Airflow selection
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Volume control switch
Press the switch to the “+” side to increase the volume. Press the switch to the “−” side to reduce the volume. A number indicating the volume will be shown on the audio display. ...