Craftsman WEEDWACKER Incredi-Pull 316.791700 Operator's Manual page 10

ROCKER ARM CLEARANCE
This requires disassembly of the engine. If unsure or unqualified to perform this,
take the unit to a Sears or other qualified service dealer.
• The engine must be cold when
checking or adjusting the valve
clearance.
This task should be performed
inside, in a clean, dust free area. Screws
1. Remove the six (6) screws on
the back of the engine cover
with a Flat-head or T-25 Torx
screwdriver (Fig. 30).
2. Disconnect the spark plug wire.
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. Remove the engine cover
(Fig. 30).
5. Clean dirt from around the
rocker arm cover. Remove
the screw holding the rocker
arm cover with a large flat
blade screwdriver or Torx T-
25 bit (Fig. 31). Remove the
rocker arm cover and gasket.
6. Pull the starter rope slowly to
bring the piston to the top of
its travel, (known as top dead
center). Check that:
The piston is at the top of its
travel. This should be done by Arms
looking into the spark plug hole.
(Fig. 31)
Both rocker arms move freely,
and both valves are closed
If these statements are not true,
repeat step 6.
7. Slide the feeler gauge between
the rocker arm and the valve
return spring. Measure the
clearance between the valve
stem and rocker arm (Fig. 33).
Measure both the intake and
exhaust valves.
The recommended clearance for
both intake and exhaust is .003 -
View of the Rear Engine Cover
Fig. 30
Screws
Spark Plug
HoNe
Fig. 31
mNTAKE
Nuts
Nut _Gaugej
0.003-0,006 in..[_._,_,_,_,_,_,_,_,_,_ V
(0.076-0.152 ram)
VaNveStem
Fig. 33
.006 in. (.076 -0.152 mm). Use a standard automotive .005 in. (0.127 mm)
feeler gauge. The feeler gauge should slide between the rocker arm and
valve stem with a slight amount of resistance, without binding. See Figures
32 and 33.
8. If the clearance is not within specification:
a. Turn the adjusting nut using a 5/16 inch (8 mm) wrench or nut driver
(Fig. 33).
To increase clearance, turn the adjusting nut counterclockwise.
To decrease clearance, turn the adjusting nut clockwise.
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,,Ib (2.2--3.4 N_ra).
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
Champion #RDZ4H spark plug. The correct air gap Use a replacement ®
is 0.025 in. (0.635 rata).
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. 34).
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.
m i
_L_ ARNING:
Do not sand blast, scrape or clean spark plug
electrodes. Grit in the engine could damage the cylinder.
4. Replace cracked, fouled or
dirty spark plug. Set the air
gap at 0.025 in. (0.635 rata)
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.
If using a torque wrench torque to:
110-120 in.olb. (12.3-13.5 Nora)
Do not over-tighten.
0.025 in.
(0.635 ram) 1'
Fig. 34
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.
Short Terra Storage (1-2 weeks)
1. Store the unit in a horizontal position. If this is not possible, store the
unit vertically with the engine at the top.
Long Terra Storage
1. Remove the fuel cap, tip the unit and drain the fuel into an approved
container.
NOTE: Do not use gasoline that has been stored for more than 30 days.
Dispose of old gasoline in accordance with 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 Off. Dispose of the old oil in
accordance with 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.
PLUG=IN POWER START AND POWER BIT =
START FEATURES
This unit can be started with an optional Plug-In
Power Start or Power Bit Start (items may be
sold separately). If choosing to start the unit
using one of these features or have questions,
please contact your local Craftsman retailer or
call 1=800=4-MY=HOME® for more information \
and purchasing. You may also go to
www.craftsman.com. Power Start Feature
ITEM NO. DESCRiPTiON
316.85951 ..................................... Plug-In Power Start
316.85952 ........................................ Power Bit Start
lO