Power Steering Vane Pump: Inspection

CHECK OIL CLEARANCE BETWEEN VANE PUMP SHAFT AND BUSHING
Using a micrometer and caliper gauge, measure the oil clearance.

Standard clearance:

0.03 - 0.05 mm (0.0012 - 0.0020 in.)

Maximum clearance: 0.07 mm (0.0028 in.)

If it is more than the maximum, replace the shaft and front housing.

Fig 1: Checking Oil Clearance Between Vane Pump Shaft & Bushing
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT VANE PUMP ROTOR AND VANE PLATES

Using a micrometer, measure the height, thickness and length of the 10 plates.
Minimum height: 8.6 mm (0.339 in.)

Minimum thickness: 1.397 mm (0.0550 in.)

Minimum length: 14.991 mm (0.5902 in.)

Fig 2: Measuring Height, Thickness And Length Of Vane Plates
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Using a feeler gauge, measure the clearance between the rotor groove and plate.
Maximum clearance: 0.033 mm (0.0013 in.)

Fig 3: Measuring Clearance Between Rotor Groove & Plate
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If it is more than the maximum, replace the plate and/or rotor with one having the same mark stamped on the cam ring.

Inscribed mark: 1, 2, 3, 4 or None

NOTE: There are 5 vane plate lengths with the following rotor and cam ring marks:

VANE PLATE LENGTHS WITH ROTOR AND CAM RING MARKS

Rotor And Cam Ring Mark	Vane Plate Part Number	Vane Plate Length mm (in.)
None	44345-26010	14.999-15.001 (0.59051-0.59059)
1	44345-26020	14.997-14.999 (0.59043-0.59051)
2	44345-26030	14.995-14.997 (0.59035-0.59043)
3	44345-26040	14.993-14.995 (0.59027-0.59035)
4	44345-26050	14.991-14.993 (0.59020-0.59027)

Fig 4: Identifying Inscribed Mark

G03146387

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.
  
  Fig 5: Installing Flow Control Valve
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the flow control valve for leakage.
  Close one of the holes and apply compressed air 392-490 kPa (4-5 kgf/cm² , 57-71 psi) into the opposite side, and confirm that air does not come out from the end holes.
  
  Fig 6: Checking Flow Control Valve For Leakage
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If necessary, replace the valve with one having the same letter as inscribed on he front housing.
  
  Inscribed mark: A, B, C, D, E or F
  
  Fig 7: Identifying Inscribed Mark
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT SPRING
Using vernier calipers, measure the free length of the spring.
1. Minimum free length: 33.2 mm (1.307 in.)
If it is not within the specification, replace the spring.

Fig 8: Measuring Free Length Of Spring
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002