Power Steering Vane Pump: Inspection

Using a micrometer and a caliper gauge, measure the oil clearance.

Standard clearance: 0.021 - 0.043 mm (0.0008 - 0.0017 in.) 

Maximum clearance: 0.07 mm (0.0028 in.) 

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

Fig 1: Measuring Oil Clearance Between Vane Pump Shaft & Bushing

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

   Minimum height: 7.6 mm (0.299 in.) 

   Minimum thickness: 1.405 mm (0.0553 in.) 

   Minimum length: 11.993 mm (0.4722 in.) 

   Fig 2: Measuring Height, Thickness & Length Of 10 Vane Plates

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2. Using a feeler gauge, measure the clearance between the vane pump rotor groove and vane plate.

   Maximum clearance: 0.025 mm (0.0010 in.) 

   Fig 3: Measuring Clearance Between Vane Pump Rotor Groove & Vane Plate

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   If it is more than the maximum, replace the vane plate and/or vane pump rotor with the one having the same mark stamped on the cam ring. See Fig 4.

   Inscribed mark: 0, 1, 2, 3, or 4 

   HINT:

   There are 5 vane plate lengths corresponding to the following vane pump rotor and cam ring marks:

   INSCRIBED MARK SPECIFICATION
   
   

   Vane pump rotor and cam ring.mark	Vane plate part number	Vane plate length mm (in.)
   0	44345 - 32100	12.001 - 12.003 (0.47248 - 0.47256)
   1	44345 - 32110	11.999 - 12.001 (0.47240 - 0.47248)
   2	44345 - 32120	11.997 - 11.999 (0.47232 - 0.47240)
   3	44345 - 32130	11.995 - 11.997 (0.47224 - 0.47232)
   4	44345 - 32140	11.993 - 11.995 (0.47216 - 0.47224)

   Fig 4: Identifying Inscribed Mark On Cam Ring

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1. Coat the flow control valve with power steering fluid and check that it falls smoothly into the valve hole of the front housing by its own weight.
   Fig 5: Checking Flow Control Valve Falls Smoothly Into Valve Hole

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2. Check the flow control valve for leakage. Close one of the holes and apply compressed air of 392 - 490 kPa (4 - 5 kgf/cm² , 57 - 71 psi) into the opposite side hole, and confirm that air does not come out from the end hole.
   Fig 6: Checking Flow Control Valve For Leakage

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   If necessary, replace the flow control valve with the one having the same letter as inscribed on the front housing.

   Inscribed mark: A, B, C, D, E or F 

   Fig 7: Identifying Inscribed Mark Location

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Using vernier calipers, measure the free length of the spring.

Minimum free length: 36.9 mm (1.453 in.) 

If it is not within the specification, replace the spring.

Fig 8: Measuring Free Length Of Spring

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