Disassembly and Assembly

Fig. 46 Exploded View Of Power Steering Pump. Supra:

Disassembly

1. Position power steering pump in suitable soft-jawed vise.
2. Remove adjust stay.
3. Remove air control valve and union seat, Fig. 46.
4. Remove suction port union and O-ring.
5. Remove pressure port union and O-ring, then remove flow control valve and spring.
6. Using suitable snap ring pliers, remove snap ring, temporarily install bolt to flow control spring seat, then remove seat and O-ring.
7. Place installation alignment marks on front and rear housing, then remove rear housing.
8. Using suitable plastic hammer, tap out end shaft, then remove rear side plate and O-ring.
9. Using suitable plastic hammer, tap out rotor shaft assembly, then remove wave washer.
10. Remove cam ring and vane plates.
11. Using suitable pliers, remove pump shaft snap ring, remove rotor and front plate from pump shaft.

Inspection & Repair

1. Using suitable micrometer and calipers, measure oil clearance between shaft and bushing, .0028 inch or less should be indicated, if not replace entire power steering pump.
2. Using suitable micrometer, measure height, thickness and length of vane plates. Minimum height should be .319 inch, thickness, .0707 inch and length .5901 inch.
3. Using suitable feeler gauge, measure clearance between rotor groove and vane plate, maximum indicated should be .0011 inch on 1989 models or .0012 inch on 1990-92 models.
4. If measurements are not as indicated in steps 2 and 3, replace vane plate and/ or rotor with one having the same mark stamped on cam ring.
5. Coat flow control valve with power steering fluid, ensuring it falls smoothly into valve hole.
6. Close one flow control valve hole, then apply compressed air (57-71 psi) to opposite side, ensuring air does not come out end holes.
7. If inspections are not as indicated in steps 6 and 7, replace flow control valve with one having same letter as on front housing.
8. Using suitable scale, measure flow control spring free length, 1.46-1.54 inch should be indicated, if not replace spring.
9. If required, replace oil seal as follows:
a. Using suitable screwdriver, pry out oil seal.
b. Using suitable socket and hammer, drive in new oil seal.

Assembly

1. Coat all sliding surfaces with power steering fluid.
2. Using suitable plastic hammer, drive short straight pin to front plate.
3. Install O-rings to front plate, then install front plate, rotor and snap ring to pump shaft.
4. Coat oil seal lip with MP grease, install long straight pin to front housing, align front plate hole and straight pin, then using suitable plastic hammer, tap in pump shaft. Do not damage oil seal and O-rings.
5. Align cam ring holes with straight pins, then install cam ring with inscribed marks facing outward.
6. Install vane plates with round end facing outward.
7. Install side plate O-ring, then align side plate holes with pins and install side plate.
8. Install rear housing wave washer, O-ring, then using suitable plastic hammer, tap in rear housing, install snap ring.
9. Ensure pump shaft rotates smoothly without noise.
10. Temporarily install pulley nut and check rotating torque, 2.4 inch lbs. or less should be indicated.
11. Install O-ring to flow control spring seat, install spring seat with bolt hole facing outward to housing, then install snap ring.
12. Install spring, flow control valve, O-ring and pressure port union, tighten to specifications.
13. Install suction port O-ring and suction port union to housing, tightening to specifications.
14. Install air control valve.
15. Install adjusting stay.