Cub Cadet CC4125 / CC4175 Operator's Manual page 12

3. Disconnect the spark plug wire.
4. Clean dirt from around the spark plug. Remove the spark
plug from the cylinder head by turning a 5/8 in. socket
counterclockwise.
5. Remove the engine cover (Fig. 35 & 36).
6. 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. 37). Remove the rocker
arm cover and gasket.
Rocker Arm Cover
Spark Plug Hole
7. 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 while looking in the
spark plug hole (Fig. 37)
• Both rocker arms move freely, and both valves are closed
If these statements are not true, repeat this step.
8. Slide the feeler gauge between the rocker arm and the
valve return spring. Measure the clearance between the
valve stem and rocker arm (Fig. 38). Measure both the
intake and exhaust valves.
Rocker Arms
INTAKE
Feeler Gauge
The recommended clearance for both intake and exhaust is
.003 – .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. Figure 38 and 39 show how to
measure the clearance.
12
MAINTENANCE AND REPAIR INSTRUCTIONS
Fig. 37
Adjusting Nuts
EXHAUST
Fig. 38
Exhaust
Adjusting Nut
0.003–0.006 in.
(0.076–0.152 mm)
Intake Valve
Stem
9. If the clearance is not within specification:
a. Turn the adjusting nut using a 5/16 inch (8 mm) wrench or
nut driver (Fig. 39).
• To increase clearance, turn the adjusting nut
counterclockwise.
• To decrease clearance, turn the adjusting nut
clockwise.
b. Recheck both clearances, and adjust as necessary.
10. Reinstall the rocker arm cover using a new gasket. Torque
the screw to 20–30 in•lb (2.2–3.4 N•m).
11. Reinstall the engine cover. Check alignment of the cover
before tightening the screws. Tighten screws.
12. Reinstall the muffler cover. Slip the rear tab on the muffler
cover into the engine cover rear slot. Then slide the
remaining slots into the tabs until they snap into place
(Fig. 33).
13. Check the spark plug and reinstall. See Replacing the
Spark Plug.
14. Replace the spark plug wire.
Exhaust
Rocker Arm
Feeler Gauge
Exhaust Valve Stem
Fig. 39