If whitish cotton-like wafts are observed, aluminum parts in the cooling system are corroded. If the coolant is brown, iron or steel parts are rusting. In either case, flush the cooling system.
If the coolant gives off an abnormal smell, check for a cooling system leak. It may be caused by exhaust gas leaking into the cooling system.

Coolant Level Inspection
Refer to the Coolant Level Inspection in the PeriodicMaintenance chapter.
Coolant Draining
Refer to the Coolant Change in the Periodic Maintenance chapter.
Coolant Filling
Refer to the Coolant Change in the Periodic Maintenance chapter.
Coolant
Pressure TestingCheck 3-3: High Beam Indicator Light (LED) Inspection
Connect the leads in the same circuit as Check 3-2.
Connect the terminal [7] to the battery (+) terminal.
Check that the high beam indicator light (LED) [A] goes
on.
If the indicator light does not go on, replace the meter unit.
...
Idle Speed Control Valve Actuator Input Voltage Inspection
NOTE
Be sure the battery is fully charged.
Turn the ignition switch to OFF.
Disconnect the idle speed control valve actuator connector
and connect a suitable measuring leads [A] between
these connectors as shown in the figure.
Main Harness [B]
Idle Speed Control Valve Actua ...
Transmission Assy Removal
Remove:
Engine Sprocket (see Engine Sprocket Removal in the
Final Drive chapter)
Gear Position Switch (see Gear Position Switch Removal
in the Electrical System chapter)
Collar [A]
O-ring [B]
Remove:
Clutch (see Clutch Removal in the Clutch chapter)
Shift Shaft Assembly ...