Yamaha YZF-R125 Service Manual: Water pump

Installing the thermostat

1. Install: Thermostat NOTE: Install the thermostat with its breather hole "a" facing up. 2. Install: Copper washer Coolant temperature sensor CAUTION:Use extreme care when ...

Disassembling the water pump

1. Remove: Water pump seal "1" NOTE: Remove the water pump seal from the inside of the water pump housing "2". 2. Remove: Bearing "1" NOTE: Remove the bearing from the outside of ...

Other materials:

Checking the cylinder head
1. Eliminate: Combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid damaging or scratching: Spark plug bore threads Valve seats 2. Check: Cylinder head Damage/scratches   Replace. Cylinder head water jacket Min ...

Checking the primary driven gear
1. Check: Primary driven gear "1" Damage/wear Replace the primary drive gear and clutch housing as a set. Excessive noise during operation  Replace the primary drive gear and clutch housing as a set. ...

Self-diagnostic function table
If the ECU detects an abnormal signal from a sensor while the vehicle is being driven, the ECU illuminates the engine trouble warning light and provides the engine with alternate operating instructions that are appropriate for the type of malfunction. When an abnormal signal is received fro ...