Special Tool - Hand Tester: 57001-1394
Charging Voltage 

If the charging voltage is kept between the values given in the table, the charging system is considered to be working normally.
If the charging voltage is much higher than the values specified in the table, the regulator/rectifier is defective or the regulator/rectifier leads are loose or open.
If the charging voltage does not rise as the engine speed increases, then the regulator/rectifier is defective or the alternator output is insufficient for the loads. Check the alternator and regulator/rectifier to determine which part is defective.
Alternator Rotor Installation
Alternator InspectionAir Switching Valve
Air Switching Valve Operation Test
Refer to the Air Suction System Damage Inspection in the
Periodic Maintenance chapter.
Air Switching Valve Unit Test
Remove the air switching valve (see Air Switching Valve
Removal in the Engine Top End chapter).
Set the hand tester [A] to the × 1 ...
Crankshaft Installation
NOTE
If the crankshaft is replaced with a new one, refer to
the Connecting Rod Big End Bearing/Crankshaft Main
Bearing Insert Selection in the Specifications.
NOTICE
If the crankshaft, bearing inserts, or crankcase
halves are replaced with new ones, select the bearing
inserts and check cleara ...
Air Suction System Damage Inspection
Separate the air switching valve hose [A] from the lower
air cleaner housing [B] (see Air Cleaner Housing Removal
in the Fuel System (DFI) chapter).
Connect the following parts temporarily.
Fuel Pump Lead Connector [A]
Extension Tube [B]
Air Cleaner Housing (see Air Cleaner Hou ...