Steering Pump Overhaul: Disassembly

Force down cover in a press and remove retainer ring. Remove cover, coil spring, and "O" ring. Remove end plate and "O" ring, noting location of pin in one of the small holes on end plate.

Fig 1: Removing End Cover
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Fig 2: Removing End Plate
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Tilt housing and remove cam ring and rotor. Note that side of rotor with recessed hole faces drive shaft, the rounded off side of rotor faces cam ring, and the cast-in half arrow indicates direction of rotor rotation.

Fig 3: Pin Location
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Remove lower end plate and "O" ring. If it should be necessary to remove drive shaft, proceed as follows: Remove pulley, remove retainer ring from housing, then force out drive shaft. Inspect seal and needle roller bearing and replace if necessary.
NOTE: Installed depth of needle roller bearing is 1.457" + 0.008" (37 + 0.2 mm).

Replace ball bearing on drive shaft if necessary.

Fig 4: Recessed Side Of Rotor
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Fig 5: Rotation Marking
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Fig 6: "O" Ring Locations
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Remove plug from pressure valve bore, then remove coil spring and valve piston. Note that threaded section on valve piston faces coil spring.
CAUTION: Do not alter length of coil spring or thickness of plug sealing ring.

Fig 7: Pump Drive Shaft
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The valve tolerance group (1 or 2) is stamped into housing adjacent to pressure valve bore and valve barrel should be scribed with one or two marks (lines) agreeing with group number stamped into housing.
CAUTION: If valve must be replaced, install valve of same tolerance group.

Fig 8: Oil Seal & Needle Roller Bearing
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Clean and inspect all parts. Clean restrictor insert in pump outlet passage. Valve piston may be disassembled for cleaning.
CAUTION: When disassembling piston, do not clamp across the sliding surfaces.

A pressure valve is located inside valve piston (flow limit valve), and thickness of washers determines cut-in range of pressure valve. Maximum pump pressure should not be more than 10% below the value stated on manufacturer's plate attached to pump.

Fig 9: Needle Roller Bearing Location
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Fig 10: Pump Valve Plug & Spring
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Clean power steering reservoir, wipe dry with lint free cloth, and install new filter element.