Power Steering Vane Pump: Inspection

1. Standard clearance: 0.03 - 0.05 mm (0.0012 - 0.0020 in.)  .
2. Maximum clearance: 0.07 mm (0.0028 in.)  .

Fig 1: Measuring Vane Pump Shaft To Bushing Oil Clearance

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

1. Using a micrometer, measure the height, thickness and length of the 10 vane plates.
   1. Minimum height: 8.6 mm (0.339 in.)  .
   2. Minimum thickness: 1.397 mm (0.05500 in.)  .
   3. Minimum length: 14.991 mm (0.59016 in.)  .
   Fig 2: Measuring Vane Plates

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NOTE: HINT: There are 5 vane plate lengths corresponding to the following vane pump rotor and cam ring marks: Inscribed mark: 1, 2, 3, 4 or None  .
Fig 3: Locating Rotor & Cam Ring marks
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Fig 4: Measuring Rotor Groove & Plate Clearance
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Fig 5: Rotor & Cam Ring Identification/Specifications Chart
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2. Using a feeler gauge, measure the clearance between the vane pump rotor groove and vane plate. Maximum clearance: 0.03 mm (0.0012 in.)  .

   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.

1. Coat the valve with power steering fluid and check that it falls smoothly into the valve hole by its own weight.
   Fig 6: Inspecting Flow Control Valve

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NOTE: Install a new flow control valve with the same inscribed mark as the old one. Inscribed mark: A, B, C, D, E or F  .
Fig 7: Locating Flow Control Valve Marks
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Fig 8: Testing Flow Control Valve
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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.

   If necessary, replace the flow control valve.

Using vernier calipers, measure the free length of the spring. Minimum free length: 33.2 mm (1.307 in.)  .

If it is less than the minimum, replace the spring.

Fig 9: Measuring Flow Control Valve Spring Length

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