Honda HRC216PDA Owner's Manual page 39

5. Install the spark plug carefully,
by hand, to avoid
cross-threading.
6. After the spark plug seats,
tighten with a 13/16 in (21 mm)
spark plug wrench to compress
the washer.
If reinstalling the old spark plug,
tighten 1/8 to 1/4 turn after the
spark plug seats.
If installing a new spark plug,
tighten 1/2 turn after the spark
plug seats to compress the washer.
NOTICE
A loose spark plug can overheat and damage the engine.
Overtightening the spark plug can damage the threads in the
cylinder head.
7. Install the spark plug cap on the spark plug.
SERVICING YOUR LAWN MOWER
0.028 ~ 0.031 IN
(0.7 ~ 0.8 MM)
SEALING
WASHER
37