Adjusting Nut
.003–.006 in.
(.076–.152 mm)
12. Reinstall the engine cover. Check alignment of the cover
before tightening the screws. Tighten screws.
REPLACING THE SPARK PLUG
Use a replacement part number 753-05255 or Champion spark
plug, #RDZ19H. The correct air
gap is 0.025 in. (0.635 mm).
Remove the plug after every 25
hours of operation and check its
condition.
1. Stop the engine and allow it
to cool. Remove the six (6)
screws on the back of the
engine cover with a Flat-
head or T-25 Torx
screwdriver (Fig. 30).
2. Grasp the plug wire firmly
and pull the cap from the spark plug.
3. Clean dirt from around the spark plug. Remove the spark
plug from the cylinder head by turning a 5/8 in. socket
counterclockwise.
4. Replace cracked, fouled or dirty spark plug. Set the air gap
at 0.025 in. (0.635 mm) using a feeler gauge (Fig. 34).
5. Install a correctly-gapped spark plug in the cylinder head.
Turn the 5/8 in. socket clockwise until snug.
WARNING:
Do not sand blast, scrape or clean
electrodes. Grit in the engine could damage the
cylinder.
If using a torque wrench torque to:
110-120 in.•lb. (12.3-13.5 N•m)
Do not over tighten.
SPARK ARRESTOR MAINTENANCE
1. Remove the rear engine cover. See Rocker Arm Clearance.
2. With a flat blade screwdriver or Torx T-20 bit and a T-25
bit, remove the screws attaching the spark arrestor diverter
to the muffler (Fig. 35).
3. Pull the the spark arrestor diverter out of the muffler.
Remove the spark arrestor diverter.
4. Remove the spark arrestor screen from the spark arrestor
diverter.
WARNING:
To avoid serious personal injury,
always turn your unit off and allow it to cool before
you clean or service it.
MAINTENANCE AND REPAIR INSTRUCTIONS
Rocker Arm
Feeler Gauge
Valve Stem
Fig. 33
0.025 in.
(0.635 mm)
Fig. 34
Muffler
Slot
5. Clean the spark arrestor screen with a wire brush or
replace it.
6. Reinstall the spark arrestor screen, spark arrestor diverter
and screws.
CLEANING
Use a small brush to clean off the outside of the unit. Do not
use strong detergents. Household cleaners that contain
aromatic oils such as pine and lemon, and solvents such as
kerosene, can damage plastic housing or handle. Wipe off any
moisture with a soft cloth.
STORAGE
• Never store the unit with fuel in the tank where fumes may
reach an open flame or spark.
• Allow the engine to cool before storing.
• Lock up the unit to prevent unauthorized use or damage.
• Store the unit in a dry, well-ventilated area.
• Store the unit out of the reach of children.
LONG TERM STORAGE
1. Drain all gasoline from the gas tank into a container. Do
not use gas that has been stored for more than 60 days.
Dispose of the old gasoline in accordance to Federal,
State, and Local regulations.
2. Start the engine and allow it to run until it stalls. This
ensures that all gasoline has been drained from the
carburetor.
3. Allow the engine to cool. Remove the spark plug and put 5
drops of high quality motor oil into the cylinder. Pull the
starter rope slowly to distribute the oil. Reinstall the spark
plug.
NOTE: Remove the spark plug and drain all of the oil from the
cylinder before attempting to start the trimmer after
storage.
4. Change the oil, referring to Changing the Oil. Dispose of
the old oil in accordance to Federal, State and Local
regulations.
5. Thoroughly clean the unit and inspect for any loose or
damaged parts. Repair or replace damaged parts and
tighten loose screws, nuts or bolts. The unit is ready for
storage.
TRANSPORTING
• Allow the engine to cool before transporting.
• Secure the unit while transporting.
• Drain the gas tank before transporting.
• Tighten gas cap before transporting.
13
Spark Arrestor Screen
Diverter
T-25 Screw
T-20 Screw
Fig. 35