Craftsman 316.7948 - Manual (Page 13)

13
MAINTENANCE AND REPAIR INSTRUCTIONS
b. Recheck both clearances, and adjust as necessary.
9. Reinstall the rocker arm cover using a new gasket. Torque the
screw to 20–30 in•lb (2.2–3.4 N•m).
10. Check the spark plug and reinstall. See Replacing the Spark Plug.
11. Replace the spark plug wire.
12. Reinstall the engine cover. Check alignment of the cover
before tightening the screws. Tighten screws.
REPLACING THE SPARK PLUG
Use a Champion RDZ19H or a replacement part number 753-05255
spark plug. 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 eight (8)
screws on the back of the engine cover with a Flat-head or T-
25 Torx screwdriver (Fig. 31).
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. 35).
5. Install a correctly-gapped spark
plug in the cylinder head. Turn
the 5/8 in. socket clockwise until snug.
0.025 in.
(0.635 mm.)
Fig. 35
Fig. 34
Feeler Gauge
Adjusting Nut
Rocker Arm
.003–.006 in.
(.076–.152 mm)
Valve Stem
If using a torque wrench torque to:
110-120 in.•lb. (12.3-13.5 N•m)
Do not over tighten.
SPARK ARRESTOR MAINTENANCE
Inspect the spark arrestor after every 50 hours of operation.
1.
Remove the rear engine cover. See Rocker Arm Clearance.
2. With a flat blade screwdriver, or a Torx T-20 bit and a T-25 bit, remove
the 2 screws attaching the spark arrestor cover to the muffler (Fig. 36).
3. Pull the tab on the spark arrestor cover out of the muffler.
Remove the spark arrestor cover.
4. Remove the spark arrestor screen from the spark arrestor cover.
5. Clean the spark arrestor screen with a wire brush or replace it.
6. Reinstall the spark arrestor screen, spark arrestor cover, 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 seven (7) screws on the
back of the engine cover with a Flat-head or T-25 Torx
screwdriver. 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 blower 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.
WARNING: Do not sand blast, scrape or clean
electrodes. Grit in the engine could damage the cylinder.
WARNING: To avoid serious personal injury, always
turn your unit off and allow it to cool before you clean
or service it.
Intake Valve
Stem
Fig. 36
Muffler
Spark Arrestor Screen
Spark Arrestor Cover T-20 Screw
Slot
T-25 Screw
Adjusting Nuts
Feeler Gauge
Rocker Arms
Fig. 33
INTAKE
EXHAUST
Spark Plug Hole