Exmark 312 Lawn Mower User Manual


 
Maintenance
Figure 30
Left Hand Brake Shown
1. Cable anchor 5. Caliper
2. Hold threaded rod here
6. Compression spring
3. Measure 7. Threaded rod
4. Lock nut 8. Hub
10. Disengage the park brake. Turn the wheel hub
by hand in both directions relative to the caliper;
no drag of the caliper pad on the wheel hub is
desired.
11. If there is no movement between the hub and the
caliper then repeat the adjustment (drive release
valves must be in the “released” position on the
hydros).
12. After adjusting the brakes on both sides of the
mower, cycle the brake handle a minimum of six
times to allow the cable to seat into the sheath
and mounting tabs.
13. Recheck the spring length; engage the park brake
and repeat steps
8 through 11 if the length is not
in the correct range.
14. Rotate the drive wheel release handle to the
“operating” position. Refer to the Drive Wheel
Release Valves section in Operation.
15. Install the rear tires and torque lug nuts to 90-95
ft-lb (122-129 N-m).
16. Remove jack stands.
Electric Clutch Adjustment
No adjustment necessary. However when the clutch
brake has worn to the point where the clutch no
longer engages consistently, the shim can be removed
to extend the clutch life.
Figure 31
1. Armature 5. Brake spacer
2. Field shell 6. Re-gap shim
3. Rotor 7. Brake pole
4. Brake mounting bolt
Removing the Shim:
1. Stop engine, wait for all moving parts to stop,
and remove key. Engage parking brake. Allow
the machine to cool completely before starting
these instructions.
2. Using a pneumatic line, blow out any debris
from under the brake pole and around the brake
spacers.
3. Check the condition of the wire harness leads,
connectors, and terminals. Clean or repair as
necessary.
4. Verify that 12V is present at the clutch connector
when the PTO switch is engaged.
5. Measure the gap between the rotor and armature.
If the gap is greater than .04 inch (1 mm), proceed
with the following steps:
A. Loosen both brake mounting bolts one-half
to one full turn (see
Figure 32).
Note: Do Not remove the brake pole from
the eld shell/armature. The brake pole has
worn to match the armature and needs to
continue to match after the shim is removed
to ensure proper brake torque.
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