14
1. Allow the engine to cool,
disconnect the spark plug
cap, and remove any dirt
from around the spark
plug area.
2. Remove the spark plug
with a 13/16 in (21 mm)
spark plug wrench.
3. Inspect the spark plug.
Replace it if the
electrodes are worn, or if
the insulator is cracked or
chipped.
4. Measure the spark plug
electrode gap with a
suitable gauge.
Gap:
0.028 ~ 0.031 in
(0.7 ~ 0.8 mm)
Correct the gap, if
necessary, by carefully
bending the side
electrode.
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.
Spark plug torque: 14 ft-lb (20 N·m)
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.
Spark Arrester (optional part)
The spark arrester must be serviced every 100 hours to keep it
functioning as designed.
Your lawn mower engine is not factory-equipped with a spark arrester.
In some areas, it is illegal to operate an engine without a spark
arrester. Check local laws and regulations. An optional USDA
approved spark arrester is available from an authorized Honda
servicing dealer. See “Parts, Accessories, and Service Items” on
for the part number.
1. Allow the engine to cool.
2. Unclip the two red top cover tabs [6] on the muffler side of the
engine, and then slightly lift the red top cover up to expose the
upper muffler shield bolt.
3. Remove the three bolts [1] from the muffler shield [2] using a
10 mm socket wrench.
4. Remove the muffler shield [2].
5. Remove the set screw [4].
6. Remove the spark arrester [3] from the muffler [5].
7. Check for carbon deposits on the spark arrester and the exhaust
port. Brush carbon deposits away. Be careful to avoid damaging
the spark arrester screen.
8. Install the spark arrester into the muffler.
9. Install the muffler components on the engine, and tighten the three
bolts securely.
Blade Control Check
1. Start the engine outdoors.
2. Release the blade control
lever; the engine should
stop quickly.
If it does not, take your
mower to an authorized
Honda servicing dealer for
repair.
SPARK PLUG
SPARK
PLUG
CAP
0.028 ~ 0.031 in
(0.7 ~ 0.8 mm)
SEALING
WASHER
[4]
[3]
[1] (3)
[2]
[5]
[6]
(red cover shown removed)
BLADE
CONTROL
LEVER
