If the surface is corroded or if the blades are damaged, replace the impeller

Water Pump Impeller Disassembly/Assembly
Water Pump Housing DisassemblyValve Clearance Adjustment
To change the valve clearance, remove the camshafts
(see Camshaft Removal in the Engine Top End chapter)
and valve lifters.
Replace the shim with one of a different thickness.
NOTE
Mark and record the locations of the valve lifters and
shims so that they can be reinstalled in their ...
Special Tools and Sealant
Hand Tester:
57001-1394
Flywheel Puller Assembly, M38 × 1.5/M35 × 1.5:
57001-1405
Peak Voltage Adapter:
57001-1415
Lead Wire - Peak Voltage Adapter:
57001-1449
Key Registration Unit:
57001-1582
Grip:
57001-1591
Flywheel & Pulley Holder:
57001-1605
Rotor Holder:
...
Master Cylinder Rubber Parts Replacement
Front Master Cylinder Disassembly
Remove the front master cylinder (see Front Master Cylinder
Removal in the Brakes chapter).
Remove the seal cover [A], circlip [B], connector [C] and
O-ring [D].
Special Tool - Inside Circlip Pliers: 57001-143
Unscrew the locknut [E] and pivot bolt ...