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

Water Pump Impeller Disassembly/Assembly
Water Pump Housing DisassemblyRear Caliper Removal
Remove:
Bolt [A]
Rear Wheel Rotation Sensor [B]
Loosen the banjo bolt [C] at the brake hose lower end,
and tighten it loosely.
Loosen the caliper holder pin [D].
Remove the rear wheel (see Rear Wheel Removal in the
Wheels/Tires chapter).
Unscrew the banjo bolt and remove t ...
Upper Fairing Assembly Removal
Remove:
Lower Fairings (see Lower Fairing Removal)
Center Inner Fairing (see Center Inner Fairing Removal)
Upper Inner Fairings (see Upper Inner Fairing Removal)
Windshield (see Windshield Removal)
Disconnect the front turn signal light lead connector [A]
(both sides).
Remove the bo ...
Alternator Inspection
There are three types of alternator failures: short, open
(wire burned out), or loss in rotor magnetism. A short or
open in one of the coil wires will result in either a low output,
or no output at all. A loss in rotor magnetism, which may be
caused by dropping or hitting the alternator, by leav ...