RedMax G621AVS - Manual (Page 19)

4. Spark plug (F32)
Clean the electrodes with a wire brush and reset
the gap to 0.65 mm as necessary.
Champion: CJ-7Y
or
NGK: BPM7A
5. Sprocket (F33)
Check for cracks and for excesslve wear interfenng
with the chain drive. If the wearing is found
obviously, replace it with new one. Never fit a new
chain on a worn sprocket, or a worn chain on a
new sprocket.
6. Spark arrester
Remove the front Cover of the muffler and inspect
the spark arresting screen. Brush off Carbon
deposits as necessary. Replace if damaged.
• When servicing the spark arrester, refer to the
Service Parts List supplied with the unit for its
location and correct assembly order of parts.
• Be sure to use a correct tool for the muffler nuts.
The nuts are tightened firmly, and the use of
inadequate tool will damage them.
7. Front and Rear dampers
Replace if adhered part is peeled or crack is
observed on the rubber part.
Replace if the inside of the rear damper metal has
been beaten by the stopper bolt and the clearance
of the metal increased.
NOTE
9. Maintenance
F33
19 
F32