1. Using micrometer, measure diameter of pump shaft. Using calipers, measure diameter or pump housing
shaft bushing. Determine amount of clearance. Clearance should be .0012-.0020" (.030-.050 mm).
Clearance should not exceed .0028" (.071 mm). If clearance exceeds maximum specification, replace
front housing and pump shaft.
2. Using micrometer, measure height, thickness and length of 10 vane plates. See
VANE PLATE
SPECIFICATIONS
table. Use feeler gauge to measure clearance between rotor groove and plate.
Maximum clearance is .0014" (.035 mm). If clearance exceeds maximum, replace plate and/or rotor with
one having same mark stamp of "1", "2", "3", "4" or no marking.
3. Coat flow control valve with power steering fluid and check that it falls smoothly into valve hole on its
own weight.
4. Check flow control valve for leakage by closing one hole and applying 57-71 psi (4-5 kg/cm2) air
pressure to opposite hole. Air should NOT come out hole on end of valve. If valve does not respond as
indicated, replace valve with one having same letter mark as on front housing and/or on valve.
5. Using calipers, measure free length of flow control valve spring. Minimum free length is 1.272" (32.3
mm). If not within specification, replace spring.
6. If necessary, remove oil seal from housing. Coat NEW seal lip with power steering fluid and carefully
press NEW oil seal into position. Ensure seal is in same direction as removed.
Reassembly
1. Coat all internal components with power steering fluid. Install pump shaft. Install 2 NEW straight pins
into front housing.
2. Align holes of cam ring and 2 straight pins, and install cam ring with mark facing outward. Install pump
rotor with mark facing outward. Install NEW snap ring on pump shaft. Install 10 vane plates, with round
end facing outward.
3. Install a NEW gasket on housing. Install side plate. Install wave washer so protrusions fit into slots in side
plate.
4. Coat 2 NEW "O" rings with power steering fluid. Install "O" rings into pump rear housing. Install rear
housing and tighten bolts to specification. See
TORQUE SPECIFICATIONS
.
5. Install flow control spring and valve. Ensure valve is facing correct direction. Coat a NEW "O" ring with
power steering fluid. Install "O" ring to pressure port union. Tighten union to specification. See
TORQUE SPECIFICATIONS
.
6. Coat a NEW "O" ring with power steering fluid. Install "O" ring to suction (return) port union. Tighten
union bolt to specification. See
TORQUE SPECIFICATIONS
.
7. Install pump brackets. Position and hold pump pulley and install nut. Tighten nut to specification. See
TORQUE SPECIFICATIONS
. Measure pump rotating torque. Using a torque wrench, check pump
rotating torque. Rotating torque should be 2.4 INCH lbs. (.3 N.m) or less.
Disassembly (Tacoma & 4Runner 4-Cylinder)
1. Mount pump assembly in soft-jaw vise. Ensure pump rotates smoothly. Using a torque wrench, check
pump rotating torque. Rotating torque should be 2.4 INCH lbs. (.3 N.m) or less.
2. While holding pulley, remove pulley nut. Remove pulley from pump shaft. Remove fluid reservoir.
Remove and discard "O" ring.
1999 Toyota RAV4
1999-2000 STEERING Power Rack & Pinion - Trucks
Microsoft
Sunday, November 22, 2009 10:35:46 AM
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© 2005 Mitchell Repair Information Company, LLC.
