Power Steering Vane Pump: Inspection

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

Fig 1: Checking Oil Clearance Between Vane Pump Shaft And Bushing

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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.

1. Using a micrometer, measure the height, thickness and length of the 10 plates.
   Fig 2: Measuring Height, Thickness And Length Of Vane Plate

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   Minimum height: 8.6 mm (0.339 in.) 

   Minimum thickness: 1.397 mm (0.0550 in.) 

   Minimum length: 14.991 mm (0.5902 in.) 

2. Using a feeler gauge, measure the clearance between the rotor groove and plate.
   Fig 3: Measuring Clearance Between Rotor Groove And Vane Plate

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   Maximum clearance: 0.033 mm (0.0013 in.) 

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

   Fig 4: Locating Mark On Plate And/Or Rotor And Cam Ring

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   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, ROTOR AND CAM RING SPECIFICATIONS
   
   

   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)

1. Coat the valve with power steering fluid and check that it falls smoothly into the valve hole by its own weight.
   Fig 5: Checking Flow Control Valve Fitting

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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

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

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

   Fig 7: Checking For Similar Inscribed Letters

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

Fig 8: Measuring Free Length Of Spring

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Minimum free length: 33.2 mm (1.307 in.) 

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