Honda GCV520 Owner's Manual page 36

SERVICING YOUR ENGINE
3. Use a brush to remove carbon deposits from the spark arrester
screen. Be careful to avoid damaging the screen.
The spark arrester must be free of breaks and holes. Replace the
spark arrester if it is damaged.
SPARK ARRESTER SCREEN
4. Install the spark arrester, and muffler protector in the reverse order
of disassembly.
34