OEM 2003 Toyota Sienna Power Steering Pump

2003 Toyota Sienna Parts Questions & Experts Answers

• Q: How to service and repair the power steering pump on 2003 Toyota Sienna?

  A: The first step in servicing and repairing the power steering pump requires measuring the PS vane pump rotating torque while monitoring proper pump rotation with minimum torque at 0.3 Nm (2.8 kgf-cm, 2.4 inch lbs.). Stop the vane pump pulley from rotation using Special Service Tool: 09960-10010 (09962-01000, 09960-01000) before removing the front and rear brackets by taking out 3 bolts as well as 2 nuts. Then disconnect the suction port union by extracting its bolt and O-ring while moving onto the pressure port union and flow control valve and spring while collecting O-rings from the pressure port union. To continue with the disassembling sequence detach the rear housing through four bolt removal and extraction of two O-rings followed by wave washer removal alongside the side plate and gasket and cam ring and final removal of 10 vane plates with care for dropped vane plates. To access the front housing components the technician must first remove the vane pump shaft together with the two straight pins. The oil clearance measurement requires a micrometer and caliper gauge for inspection between the bushing and vane pump shaft with standard 0.03 - 0.05 mm (0.0012 - 0.0020 inch) and maximum 0.07 mm (0.0028 inch) clearance. Replace the front housing and vane pump shaft when necessary. The inspection of vane pump rotor and vane plates should focus on measuring minimum height of 8.6 mm (0.339 inch) with minimum thickness of 1.397 mm (0.0550 inch) and minimum length of 14.991 mm (0.5902 inch). The maximum allowable clearance between rotor groove and plate should be 0.035 mm (0.0014 inch). The power steering fluid should be used to coat the flow control valve before testing the smooth release into the hole as well as checking for leaks by using compressed air. The valve requires replacement if marked A, B, C, D, E or F. The spring free length measurement with vernier calipers must meet a minimum threshold of 32.3 mm (1.272 inch) to avoid replacement when specifications are not met. Use Special Service Tool: 09950-60010 (09951-00330), 09950-70010 (09951-07100) with correct installation direction to install a new oil seal after you carefully remove the old seal using a vinyl-taped screwdriver and wet the oil seal lip with power steering fluid. Reassemble the parts by applying power steering fluid to components with arrows and placing the vane pump shaft followed by hammering two new straight pins with a plastic hammer. First position the cam ring holes to match straight pins before mounting it outward from the rotor inscribed side followed by a new snap ring application. Place the 10 vane plates with rounded edges outside before fitting them with a fresh gasket and the side plate which must align with the straight pins. Fasten the wave washer by aligning its protrusions inside the side plate slots while applying power steering fluid to 2 new O-rings before installing them to the rear housing with 4 bolts tightened to 17 Nm (170 kgf-cm, 12 ft. lbs.). The success of this assembly requires proper orientation of the flow control valve while use of a torque wrench to tighten the pressure port union to a specified torque of 83 Nm (850 kgf-cm, 62 ft. lbs.). Install the spring and flow control valve and pressure port union by applying a new O-ring that received power steering fluid coating before tightening to 83 Nm. The installation process starts with attaching the suction port union at 13 Nm (130 kgf-cm, 9 ft. lbs.) torque using a new O-ring. The installation continues with the front and rear bracket assembly of 3 bolts and 2 nuts at 43 Nm (440 kgf-cm, 32 ft. lbs.) torque. After stopping the pulley rotation using Special Service Tool: 09960-10010 (09962-01000, 09963-01000) install the vane pump pulley and nut to the vane pump shaft while torquing the nut to 43 Nm (440 kgf-cm, 32 ft. lbs.) before checking the PS vane pump rotating torque.