If the disc has worn past the service limit, replace it.
Measuring Area [B]
Brake Disc Thickness Standard:
Front 5.3 
5.7 mm (0.21
0.22 in.)
Rear 4.8 
5.2 mm (0.19
0.20 in.)
Service Limit:
Front 5.0 mm (0.20 in.)
Rear 4.5 mm (0.18 in.)
Brake Disc Installation
Brake Disc Warp InspectionArmature Inspection
Using the × 1 Ω hand tester range, measure the resistance
between any two commutator segments [A].
Special Tool - Hand Tester: 57001-1394
If there is a high resistance or no reading (∞) between any
two segments, a winding is open and the starter motor
must be replaced.
...
Starter Motor Disassembly
Remove the starter motor (see Starter Motor Removal).
Take off the starter motor through bolts [A] and remove
the both end covers [B].
Pull out the armature [A] out of the yoke [B].
NOTE
Do not remove the circlip [C] from the shaft.
Remove the starter motor terminal lock ...
Thermostat Installation
Replace the O-rings [A] with new ones, and apply grease
to them.
Assemble:
O-rings
Thermostat Housing [B]
Thermostat [C]
Thermostat Cap [D]
Install the thermostat [A] in the housing so that the air
bleeder hole [B] is on top.
Tighten:
Torque - Thermostat Cap Bolts: 5.9 N ...