Air Filter Maintenance; Idle Speed Adjustment; Rocker Arm Clearance - Craftsman 316.773800 Operator's Manual

AiR FILTER MAINTENANCE
Cleaning the Air Filter
Clean and re-oil the air filter per
the Maintenance Schedule. It is an
important item to maintain. Failure
to maintain the air filter properly
can result in poor performance or
can cause permanent damage to
the engine.
1. Open the air filter cover.
Unscrew the knob on the left
side of the cover. Swing the
cover out (Fig. 23).
2. Remove the air filter (Fig. 23).
3. Wash the filter in detergent
and water (Fig. 24). Rinse the
filter thoroughly and allow it
to dry.
4. Apply enough clean SAE 30
motor oil to lightly coat the
filter (Fig. 25).
5. Squeeze the filter to spread
and remove excess oil (Fig. 26).
6. Replace the filter (Fig. 23).
NOTE: Operating the unit
without the air filter, will
VOID the warranty.
7. Make sure the back plate is
correctly positioned (Fig. 23).
8. Swing the air filter cover
closed and tighten the knob
(Fig. 23).
iDLE SPEED ADJUSTMENT
The idle speed of the engine is
adjustable. An idle adjustment
screw is between the air filter
cover and the engine starter
housing (Fig. 27).
NOTE: Careless adjustments can
seriously damage the
unit. Aside from idle
Air Filter Air Filter Cover Knob
Back Plate
Hooks
Fig. 23
Fig. 24
Fig. 25
speed, only a Sears or Fig. 26
other qualified service dealer should make carburetor adjustments.
If, after checking the fuel and cleaning the air filter, the engine still will not
idle, adjust the idle speed screw as follows:
__ I WARNING:
The blade may spin during idle speed adjustments.
Wear protect ve c oth ng and observe a safety nstruct ons to |
prevent serious personal injury.
J
1. Start the engine and let it run at a high idle for a minute to warm up.
Refer to Starting/Stopping Instructions.
2. Release the throttle lever and
let the engine idle. If the Idme Adjustment
engine stops, insert a small Screw
Phillips in between the air
filter cover and the engine
cover (Fig. 27). Turn the idle
speed screw in, clockwise,
1/8 of a turn at a time (as
needed) until the engine idles
smoothly.
NOTE: The blade should not Fig. 27
rotate when the engine
idles.
3. If the blade rotates when the engine idles, turn the idle speed screw
counterclockwise 1/8 of a turn at a time (as needed), to reduce idle
speed.
Checking the fuel, cleaning the air filter, and adjusting the idle speed should
solve most engine problems. If not and any of the following are true have the
unit serviced by a Sears or other qualified service dealer:
• the engine will not idle
the engine hesitates or stalls on acceleration
there is a loss of engine power
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.
NOTE: Inspect the valve to rocker arm clearance with a feeler gauge per
the Maintenance Schedule.
The engine must be cold when checking or adjusting the valve clearance.
This task should be performed inside, in a clean, dust free area.
1. Remove the six (6) screws on the back of the engine cover with a Flat-
head or T-25 Torx screwdriver (Fig. 28).
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. 28).
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. 29). 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 View of the Rear
Engine
Cover
looking into the spark plug hole.
(Fig. 29)
Both rocker arms move freely, Screws
and both valves are closed Screws
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
Fig. 28
clearance between the valve
stem and rocker arm (Fig. 31). Screw --______@
Measure both the intake and
exhaust valves. Rocker Arm
The recommended clearance for Cover
both intake and exhaust is .003 -
.006 in. (.076 - 0.152 ram}. Use a Spark Plug
standard automotive .005 in. Hole
(0.127 mm) feeler gauge. The
feeler gauge should slide between
the rocker arm and valve stem
with a slight amount of resistance, Fig. 29
without binding (Fig. 30 and 31). Adjusting Nuts
8. If the clearance is not within
specification: INTAKE
a. Turn the adjusting nut using a
5/16 inch (8 mm) wrench or EXHAUST
nut driver (Fig. 31). Rocker
To increase clearance, turn Arms
the adjusting nut
counterclockwise.
To decrease clearance, turn Fig. 30
the adjusting nut clockwise.
b. Recheck both clearances, Exhaust Rocker Arm
Adjusting --_
and adjust as necessary. Nut __ Feeler
9. Reinstall the rocker arm _ Gauge
cover using a new gasket. -'_ _[_4_ ,
Torque the screw to 20-30 _/
0.003-0.006 in.
inolb (2.2-3.4 Nora). (0.076-0.152 ram)
10. Check the spark plug and
reinstall. See Replacing the
Spark Plug. _ Valve Stem
11. Replace the spark plug wire. Fig. 31
12. Reinstall the engine cover. Check alignment of the cover before tightening
the screws. Tighten screws.