Power Steering Pump: Inspection

Check all parts for wear or damage and replace as necessary. Check oil clearance between pump housing bushing and rotor shaft. See Fig 1. If difference is greater than .0028" (.07 mm), replace complete pump assembly. Discard all "O" rings and replace with new ones.

Fig 1: Checking Pump Housing Bushing-to-Rotor Shaft Clearance
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Measure difference between cam ring and rotor. Maximum difference should be .0024" (.06 mm). Replace cam ring with one that has same letter stamped on rotor (if necessary).
Check vane plates for wear or damage. Celica, Supra and Van vane plate dimensions should be .589 x .307 x .067" (14.97 x 7.80 x 1.70 mm). All other models vane plate dimensions should be .590 x .319 x .070" (14.99 x 8.10 x 1.79 mm).
Maximum clearance between vane plate and rotor groove is .0024" (.06 mm) for Celica, Supra and Van. For all other models, clearance is .0011" (.028 mm).
Check flow control valve for leakage with compressed air. See Fig 2. On Celica, Supra and Van models, minimum control valve spring length is 1.85" (47 mm). On all others, control valve spring length is 1.85-1.97" (47-50 mm).

Fig 2: Checking Flow Control Valve

Fig 3: View of Power Steering Pump Rotor & Cam Ring Marks