Yamaha YZF-R125 Service Manual: Assembling the water pump

1. Install:

  • Water pump seal "1"
    (into the water pump housing "2")
CAUTION:

Never lubricate the water pump seal surface with oil or grease.

NOTE:

  • Install the water pump seal with the special tools.
  • Install the water pump seal with the special tools to the specified depth as shown in the illustration.

Assembling the water pump


A. Push down

3. Mechanical seal installer

4. Middle driven shaft bearing driver

Assembling the water pump


a. 0-0.5 mm (0-0.02 in)

2. Lubricate:

  • Water pump seal lip

3. Install:

  • Water pump housing gasket "1"

  • Water pump housing plate "2"
  • Impeller shaft
  • Impeller shaft retainer "3"

NOTE:

  • Before installing the impeller shaft retainer, lubricate the slit on the impeller shaft end with a thin coat of lithium-soap-based grease.
  • Install the water pump housing gasket, water pump housing plate, and impeller shaft retainer as shown in the illustration.
  • After installation, check that the impeller shaft rotates smoothly.

Assembling the water pump


    Checking the water pump
    1. Check: Water pump housing cover Water pump housing Cracks/damage Replace. Impeller shaft Cracks/damage/wear Replace. Bearing Rough movement Replace. Radiator outlet hose Crac ...

    Installing the water pump
    1. Install: Water pump assembly "1" O-rings "2" NOTE: Align the projection "a" on the impeller shaft with the slit "b" on the camshaft sprocket bolt. Lubricate the O-rings with a thi ...

    Other materials:

    Installing the primary drive gear and balancer gears
    1. Install: Balancer driven gear "1" Lock washer Balancer drive gear "2" Primary drive gear Washer "3" Balancer driven gear nut Primary drive gear nut NOTE: Align the punch mark "a" in the balancer drive gear "2" with the punch mark "b" in the balancer driven gear "1". ...

    Cast wheels
    To maximize the performance, durability, and safe operation of your vehicle, note the following points regarding the specified wheels. The wheel rims should be checked for cracks, bends or warpage before each ride. If any damage is found, have a Yamaha dealer replace the wheel. ...

    Checking the transmission
    1. Measure: Main axle runout (with a centering device and dial gauge "1") Out of specification Replace the main axle. 2. Measure: Drive axle runout (with a centering device and dial gauge "1") Out of specification Replace the drive axle. 3. Check: Transmiss ...

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