Steering Gear - Power Buick Skylark VII

DESCRIPTION

Note. Some Achieva and Grand Am vehicles are equipped with Variable Effort Steering (VES) system, identified by a solenoid on the power steering pump at the pressure line outlet. See STEERING SYSTEM - VARIABLE EFFORT article.

Pump pressurizes fluid and sends it through pump flow control valve, to rotary control valve inside rack and pinion assembly. Rotary control valve directs fluid to either side of rack piston, depending on steering wheel turning direction. Rack piston, attached to the rack, reduces turning effort by converting hydraulic pressure into linear force, moving rack left or right.

CAPACITY

System fluid capacity is 1.5 pints (.7L). Pump fluid capacity is one pint (.5L).

FLUID TYPE

Manufacturer recommends General Motors Power Steering Fluid (1050017) or an equivalent meeting G.M. Specification No. 9985010.

FLUID LEVEL CHECK

Maintain fluid level between FULL COLD and FULL HOT marks on dipstick or fluid reservoir.

HYDRAULIC SYSTEM BLEEDING

1. Raise and support front of vehicle. Ensure front tires are off ground. With engine off, use steering wheel to turn front wheels to full left position. Fill pump reservoir to FULL COLD mark.
2. Turn front wheels from side to side several times without hitting stops. Maintain pump reservoir fluid level at FULL COLD mark. When pump reservoir fluid is clear and free of bubbles, start engine and recheck fluid level. Add fluid if necessary.
3. Lower vehicle, and idle engine for 2-3 minutes. Ensure no fluid leaks exist. Road test vehicle to ensure power steering system is functioning properly. After road test, ensure fluid level is at FULL HOT mark, and system has no fluid leaks.

POWER STEERING PUMP BELT

Note. On 2.3L, power steering pump is driven directly off the end of intake camshaft.

3.1L

1. Power steering pump is driven by serpentine belt. Belt tension is maintained by automatic tensioner. Measure belt tension with belt tension gauge.
2. If tension is not as specified, check belt operating range indicated by marks on tensioner. See «SERPENTINE BELT TENSION»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power) table below. If belt is not within operating range, replace belt. If belt is within operating range, replace tensioner.

SERPENTINE BELT TENSION (1)

RACK BEARING PRELOAD

1. Raise and support front of vehicle. Center steering wheel. Loosen adjusting plug lock nut. (Scheme 3) Turn adjusting plug clockwise until it bottoms in housing. Back off adjusting plug 35-45 degrees (50-70 degrees on Cavalier and Sunfire).
2. While holding adjusting plug stationary, tighten lock nut to 50 ft. lbs. (68 N.m). Test drive vehicle, ensuring steering wheel returns to center after turning.

TROUBLE SHOOTING

Note. See the TROUBLE SHOOTING - BASIC PROCEDURES article in the GENERAL TROUBLE SHOOTING section.

HYDRAULIC SYSTEM PRESSURE CHECK

1. Disconnect high pressure line at rear of power steering pump. Connect Power Steering Analyzer (J-25323-B) between power steering high pressure line and pump fitting. Set parking brake and leave vehicle in Park or Neutral. Open valve on analyzer. Start engine. Allow system to reach operating temperature. Ensure fluid level is correct.
2. Note power steering pressure and flow at engine idle. DO NOT move steering wheel while engine is running. Pressure reading should be less than 150 psi (10.5 kg/cm 2 ). If pressure is greater than specified, stop engine and repair restrictions. CAUTION: Pump will be damaged if valve is held closed for more than 5 seconds.
3. Completely close valve for a few seconds and then open it. Do this 3 times, recording highest pressure and flow obtained each time valve is closed. If readings are greater than 1000 psi (70 kg/cm 2 ), but not within 50 psi (3.5 kg/cm 2 ) of each other, remove and clean flow control valve. Ensure flow control valve moves freely in bore.
4. If pressure readings are less than 1000 psi (70 kg/cm 2 ), replace flow control valve and recheck. If readings are still less than 1000 psi (70 kg/cm 2 ), replace rotor and vanes. If pump checks okay, leave valve open and go to next step.
5. Turn steering wheel all the way left and right. DO NOT hold steering wheel at stops for more than 5 seconds. If highest pressure and flow readings at each stop is not the same as maximum pressure and flow readings obtained in Step 3), steering gear is leaking internally. Remove steering gear and repair as necessary. Remove analyzer assembly. Fill and bleed hydraulic system. See «HYDRAULIC SYSTEM BLEEDING»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power__hydraulic-system-bleeding) under LUBRICATION.

Removal & Installation

1. Remove serpentine drive belt (except 2.3L). Disconnect pressure and return lines from pump. Remove mounting bolts. On 3.1L, support engine by oil pan. Remove engine mount. Remove pump. On some models it may be necessary to remove pump bracket with pump.
2. To install, reverse removal procedure. Tighten bolts and fittings to specification. See «TORQUE SPECIFICATIONS»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power__torque-specifications) . Fill and bleed hydraulic system. See «HYDRAULIC SYSTEM BLEEDING»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power__hydraulic-system-bleeding) under LUBRICATION.

Removal & Installation (3.1L)

1. Remove serpentine drive belt. If necessary, remove the power steering pump from the bracket to provide working space. Refer to «POWER STEERING PUMP»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power) . Remove pulley using Pulley Remover (J-37609-A), or Pulley Remover (J-25034-B) and Center Bolt Extension (J-37609).
2. Use Pulley Installer Set (J-36015) to push pulley onto pump shaft until pulley is flush with end of pump shaft. Install pump to bracket, if removed.

Removal

1. From inside passenger compartment, remove instrument panel lower trim panel. Remove upper pinch bolt from steering shaft flexible coupling at base of steering column.
2. In engine compartment, remove power steering fluid line retainer near steering gear, mounted to firewall (if equipped). On all except Cavalier and Sunfire, move power brake booster away from firewall, with master cylinder attached. On all models, raise and support vehicle. Remove front wheels. Separate tie rod ends from struts using Separator (J-24319-01). (Scheme 1)
3. Remove steering gear mounting bracket nuts, and remove brackets. Prepare drain pan. Disconnect pump-to-steering gear pressure and return fluid lines from steering gear. Move steering gear forward and out of firewall.
4. Remove lower pinch bolt from steering shaft flexible coupling. Remove coupling from steering gear pinion shaft. Remove firewall seal/boot from steering gear assembly. Remove steering gear through left wheel opening.

Installation

1. If studs were removed with mounting bracket nuts, apply Thread Lock Kit (1052624) to stud threads. Install studs into firewall and tighten to specification. See «TORQUE SPECIFICATIONS»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power__torque-specifications) .
2. To install remaining components, reverse removal procedure. Connect steering shaft coupling to steering gear before installing mounting brackets. Tighten left steering gear mounting bracket nuts first, then tighten right side. Adjust toe-in as necessary.

Scheme 1

Remove cotter pin and nut from tie rod end. Loosen tie rod end outer sleeve pinch bolt. Separate tie rod end from strut using Separator (J-24319-01). (Scheme 1) Unscrew tie rod end from sleeve, counting number of turns for installation reference.

Install tie rod end with the same number of turns as when removed. Tighten tie rod end castle nuts and sleeve pinch bolts to specification. See TORQUE SPECIFICATIONS . Install new cotter pin at castle nut. Adjust toe-in as necessary.

Disassembly

1. On vehicles with EVO, disconnect electrical connector from EVO actuator. (Scheme 2) Remove EVO actuator and "O" rings. On all vehicles, remove discharge fitting. Remove control valve assembly and flow control spring.
2. Insert punch into pump housing access hole, then push in and remove end cover retaining ring. Press gently on pulley end of shaft to remove end cover, "O" ring, pressure plate spring and pressure plate.
3. Remove shaft sub-assembly consisting of remaining components. Disassemble sub-assembly, noting component location for reassembly reference. Cut drive shaft seal with a small chisel. Remove and discard drive shaft seal.

Inspection

Inspect pump ring, vanes, thrust plate and shaft for scoring, pitting or chatter marks. Replace worn or damaged parts.

Reassembly

1. Lubricate new drive shaft seal, "O" rings and all other components with power steering fluid. Drive new seal into housing with suitable socket. (Scheme 2) Assemble shaft sub-assembly components in original locations. Ensure counterbore in center of pump rotor faces drive shaft end of pump housing.
2. Install shaft sub-assembly. Install remaining components. Press end cover in far enough to snap retaining ring into place. Position retaining ring gap at mounting boss. Install flow control valve assembly and related components. Tighten discharge fitting to specification. See «TORQUE SPECIFICATIONS»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power__torque-specifications).

Scheme 2

1. Remove and discard bolt head lock plate from inner tie rod retaining bolts. Remove tie rod bolts, one at a time, and slide tie rod out from under bolt support plate. (Scheme 3)
2. If removing both tie rods, temporarily install first tie rod bolt to keep boot and guides properly aligned before removing second bolt. Using Bushing Driver (J-29809), remove inner pivot bushing from tie rod.

Coat bushing with a light film of grease. Install inner pivot bushing into tie rod using bushing driver. Ensure the center housing cover washers are in place. (Scheme 3) Install tie rods one at a time. Tighten inner tie rod-to-rack bolts to specification. Refer to TORQUE SPECIFICATIONS. Secure tie rod bolt heads with new lock plate.

PINION SHAFT LOWER BEARING & SEAL

Note. Overhaul procedures are not available from manufacturer.

1. Remove steering gear assembly from vehicle. Ensure rack is centered. Make location mark across adjusting plug and housing for reassembly reference.
2. Remove adjusting plug lock nut, adjusting plug, spring and rack guide with "O" ring. Remove lower dust cover from housing. Remove retaining ring from top of pinion shaft housing.
3. Hold upper pinion shaft stub stationary, and remove lock nut from lower pinion shaft. Pinion teeth will be damaged if upper pinion shaft stub is not held stationary when removing lower pinion shaft lock nut.
4. Using a press, slowly press on threaded end of lower pinion shaft until it is flush with lower bearing. DO NOT remove pinion shaft assembly from housing.
5. Remove pinion shaft upper dust seal, pinion shaft seal and pinion shaft annulus bearing assembly from upper end of housing.

1. Ensure pinion shaft and valve assembly bottoms into housing. Install pinion shaft lock nut to threaded end of lower pinion shaft. Holding upper pinion shaft stub, tighten lower pinion shaft lock nut to 26 ft. lbs. (35 N.m). Install dust cover to lower housing.
2. Install pinion shaft annulus bearing onto pinion shaft and slide into housing. Install Seal Protector (J-29810) onto pinion shaft. Install pinion shaft dust seal and pinion shaft seal over protector and into housing.
3. Install retaining ring in groove in housing. Coat rack guide, "O" ring, adjusting spring and adjusting plug with lithium-base grease and install into housing. With rack centered in housing, turn adjusting plug clockwise until bottoms in housing. Back off adjusting plug 35-45 degrees (50-70 degrees on Cavalier and Sunfire). Check pinion shaft preload torque. See «TORQUE SPECIFICATIONS»(/buick/skylark/vii-1992-1998/remont/steering-gear/#steering-gear-power__torque-specifications) . To complete installation, reverse removal procedure.

STEERING RACK & PINION ASSEMBLY

Note. Overhaul procedures are not available from manufacturer.

Scheme 3

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• STEERING COLUMN
• SERPENTINE BELT TENSION
• HYDRAULIC SYSTEM BLEEDING
• TORQUE SPECIFICATIONS