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Vane Pump: Inspection

INSPECT OIL CLEARANCE
1. Using a micrometer and caliper gauge, measure the oil clearance.
  Standard clearance:
  
  0.03 to 0.045 mm (0.0012 to 0.0018 in.)
  
  Maximum clearance:
  
  0.07 mm (0.028 in.)
  
  If the clearance is greater than the maximum, replace the vane pump housing front and vane pump shaft.
  
  Fig 1: Measuring Oil Clearance
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT VANE PUMP ROTOR AND VANE PUMP PLATES

Using a micrometer, measure the height, thickness and length of the 10 vane pump plates.

Minimum length

THICKNESS CHART

Item	Specified Condition
Height	8.1 mm (0.318 in.)
Thickness	1.797 mm (0.0707 in.)
Length	14.988 mm (0.5901 in.)

If the thickness is less than the minimum, replace the vane pump.

Fig 2: Identifying Vane Pump Plate Specification

G05291736

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Using a feeler gauge, measure the clearance between the rotor groove and plate.
Maximum oil clearance:

0.028 mm (0.0011 in.)

If the oil clearance is greater than the maximum, replace the vane pump.

Fig 3: Measuring Clearance Between Side Face Of Vane Pump Rotor Groove And Vane Plate
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT FLOW CONTROL VALVE
1. Coat the valve with power steering fluid and check that it falls smoothly into the valve hole by its own weight.
  If not as specified, replace the vane pump.
  
  Fig 4: Inspecting Flow Control Valve
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the flow control valve for leakage.
  A C Close either hole A or B and apply 392 to 490 kPa (4 to 5 kgf*cm² , 57 to 71 psi) of compressed air into the opposite side. Confirm that air does not come out from the end hole C.
  
  If air leaks from hole C, replace the vane pump.
  
  Fig 5: Checking Flow Control Valve For Leakage
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT FLOW CONTROL VALVE COMPRESSION SPRING
1. Using a vernier caliper, measure the uncompressed length of the spring.
  Minimum uncompressed length:
  
  36.9 mm (1.45 in.)
  
  If the length is less than the minimum, replace the spring.
  
  Fig 6: Measuring Uncompressed Length Of Spring
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002