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

Water Pump Impeller Disassembly/Assembly
Water Pump Housing DisassemblyTransmission Assy Installation
Assemble the transmission assy (see Transmission Assy
Assembly).
Be sure that the dowel pins are in position.
Install the transmission assy on the crankcase.
Tighten:
Torque - Transmission Case Bolts: 20 N·m (2.0 kgf·m, 15
ft·lb)
Install:
Shift Shaft (see External Shift Mechani ...
Switch Inspection
Using a hand tester, check to see that only the connections
shown in the table have continuity.
Special Tool - Hand Tester: 57001-1394
For the switch housings and the ignition switch, refer to
the tables in the Wiring Diagram.
If the switch has an open or short, repair it or replace it
w ...
Piston Ring Thickness Inspection
Measure the piston ring thickness.
Use the micrometer to measure at several points around
the ring.
Piston Ring Thickness
Standard:
Top [A] 0.77 0.79 mm (0.0303
0.0311 in.)
Second [B] 0.78 0.79 mm
(0.0307 0.0311 in.)
Service Limit:
Top 0.70 mm (0.0276 in.)
Second 0.71 mm (0.0280 ...