Honda Power Products HHH25D Manuel De L'utilisateur page 53

3.Spark plug service
Recommended spark plug: CMR5H (NGK)
To ensure proper engine operation, the spark plug must be properly
gapped and free of deposits.
If the engine has been running, the muffler will be very hot, be careful
not to touch the muffler.
CAUTION:
Never use a spark plug of incorrect heat range.
1.Loosen the flange bolt with a hex wrench.
2.Remove the top cover, sliding it to the left.
Do not pull the starter grip and start the engine without the top cover.
There are rotating and hot parts under the cover.
FLANGE BOLT
TOP COVER
3.Remove any dirt from around the spark plug area.
4.Remove the spark plug cap and use the proper size spark plug
wrench to remove the spark plug.
SPARK PLUG
50
SPARK PLUG CAP