Vane Pump: Inspection

1. Using a micrometer, measure the outer diameter [a] of the vane pump shaft with pulley.
2. Using vernier calipers, measure the inner diameter [b] of the vane pump front housing bushing.
3. Calculate the oil clearance.

   Oil clearance = Inner diameter of the bushing [b] -Outer diameter of the shaft [a]

   Maximum oil clearance: 

   0.07 mm (0.0028 in.) 

   If the oil clearance exceeds the maximum, replace the vane pump assembly.

   Fig 1: Measuring Outer Diameter Of Vane Pump Shaft

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Using a micrometer, measure the thickness of the vane pump plates.

   Standard thickness: 

   1.405 to 1.411 mm (0.05531 to 0.05555 in.) 

   If the thickness is not within the specified range, replace the vane pump assembly.

   Fig 2: Measuring Thickness Of Vane Pump Plates

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Using a feeler gauge, measure the clearance between the side face of the vane pump rotor groove and the vane pump plates.

   Maximum clearance: 

   0.03 mm (0.0012 in.) 

   If the clearance exceeds the maximum, replace the vane pump assembly.

   Fig 3: Measuring Clearance Between Side Face Of Vane Pump Rotor Groove And Vane Pump Plates

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Coat the flow control valve assembly with power steering fluid and check that it falls smoothly into the flow control valve due to its own weight. If the control valve does not fall into the hole smoothly, replace the vane pump assembly.
   Fig 4: Inspecting Flow Control Valve

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the flow control valve assembly for leaks. Close one of the holes and apply compressed air, 392 to 490 kPa (4 to 5 kgf/cm² , 57 to 71 psi), into the opposite side hole, and confirm that air does not come out from the holes in the ends of the flow control valve assembly. If air leaks, replace the vane pump assembly.
   Fig 5: Checking Flow Control Valve For Leakage

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Using vernier calipers, measure the free length of the flow control valve compression spring.

   Minimum free length: 

   29.2 mm (1.150 in.) 

   If the length is less than the minimum, replace the vane pump assembly.

Fig 6: Measuring Free Length Of Flow Control Valve Compression Spring
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the union seat in the pressure port union is severely damaged, replace the vane pump assembly.

1. Check that the pump rotates smoothly without abnormal noise.
2. Temporarily install the service bolt.

   Recommended service bolt: 

   Thread diameter: 

   10 mm (0.39 in.) 

   Thread pitch: 

   1.25 mm (0.0492 in.) 

   Bolt length: 

   50 mm (1.97 in.) 

3. Using a torque wrench, check the pump rotating torque.

   Rotating torque: 

   0.27 N*m (2.8 kgf*cm, 2.4 in.*lbf) or less 

   If the rotating torque is not as specified, check the vane pump housing oil seal.

   Fig 7: Checking Pump Rotating Torque

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002