Steering Gear - Power (rwd) Cadillac Brougham I

DESCRIPTION

Saginaw rotary valve integral power steering gear contains a control valve which directs hydraulic pressure to either side of the rack piston. The rack piston converts hydraulic pressure into mechanical force.

TROUBLE SHOOTING

Refer to TROUBLE SHOOTING - BASIC PROCEDURES article in the GENERAL TROUBLE SHOOTING section.

LUBRICATION

See POWER STEERING GENERAL SERVICING article in the STEERING section.

TESTING

See POWER STEERING GENERAL SERVICING article in the STEERING section.

THRUST BEARING PRELOAD

Note. Adjust worm bearing preload first, then adjust pitman shaft over-center turning torque.

1. Remove steering gear. Using Spanner Wrench (J-7624), seat adjusting plug firmly in housing. Approximately 20 ft. lbs. (27 N.m) torque is required to seat adjusting plug. Index mark gear housing opposite one hole in adjusting plug.
2. Measure back (counterclockwise) 1/2" (13 mm) from index mark and make another index mark on housing. Turn adjuster plug counterclockwise until hole in plug is aligned with second mark on housing.
3. Install adjuster plug nut. Hold adjuster plug to maintain alignment and use a punch to peen nut.

PITMAN SHAFT OVER-CENTER TURNING TORQUE (LASH ADJUSTMENT)

1. Remove steering gear. Rotate pinion shaft back and forth to drain power steering fluid. Rotate pitman shaft adjuster screw counterclockwise until fully extended, then tighten one full turn. Rotate pinion shaft from stop to stop and count number of turns.
2. To center gear, start at either stop and turn pinion shaft back 1/2 the total number of turns. Once centered, flat on pinion shaft should face upward, parallel with side cover and master spline on pitman shaft should line up with adjuster screw.
3. Using an INCH lb. torque wrench with handle facing upward, rotate pinion shaft 45 degrees each side of center. Record highest turning torque measured on or near center.
4. To adjust over-center turning torque, loosen adjuster lock nut and turn pitman shaft adjuster screw clockwise until correct drag torque is obtained. On new steering gears (less than 400 miles), add 5-11 INCH lbs. (.6-1.2 N.m) to previously measured worm bearing preload. DO NOT exceed total steering gear preload of 18 INCH lbs. (2 N.m).
5. On used steering gears (400 miles or more), add 4-5 INCH lbs. (.5-.6 N.m) torque to previously measured worm bearing preload. DO NOT exceed total steering gear preload of 13 INCH lbs. (1.5 N.m). Prevent adjusting screw from turning and tighten adjusting lock nut to 20 ft. lbs. (27 N.m).

Scheme 7

Removal

1. Remove pitman arm. Clean exposed end of pitman shaft and end of housing. Remove pitman shaft and side cover. Remove dust seal (if present), and retaining ring.
2. Two different types of seal assemblies may be used. Either remove 2 washers, single lip seal and double lip seal or remove only one washer and seal. Use care not to score housing bore when prying out seals and washers.
3. Check housing for burrs and remove as necessary. Insert Pitman Shaft Bearing Remover (J-6278) through hole in top of housing and drive out needle bearing.

Installation

1. Lubricate new shaft seal with power steering fluid. Apply a single layer of tape to pitman arm shaft to avoid damaging seals.
2. Using Seal Installer (J-6219), install single lip seal and back-up washer. Ensure there is clearance for remaining double lip seal, back-up washer, and retaining ring. DO NOT allow seal to bottom in end of counter bore.
3. Install double lip seal and back-up washer. Provide clearance for retaining ring when installing seal. Install retaining ring, ensuring it is properly seated.

Removal & Installation

1. Disconnect negative battery cable. Remove pressure and return hoses from steering gear. Raise hoses to prevent fluid leakage. Remove intermediate shaft from steering gear. Remove pitman arm. Remove steering gear bolts and washers. Remove steering gear from vehicle.
2. To install, reverse removal procedure. Ensure steering gear is aligned as straight as possible with intermediate shaft. Tighten attaching bolts to 70 ft. lbs. (95 N.m).

Scheme 8

Disassembly

1. Remove steering gear from vehicle. Clean gear exterior and drain fluid. Mount gear in soft-jawed vise with pitman shaft facing down. Remove lash adjustment nut. Remove side cover bolts. Rotate pinion shaft to center gear. Remove side cover, gasket and pitman shaft assembly.
2. Remove housing end plug retaining ring. Remove plug and "O" ring seal. Rotate pinion shaft counterclockwise until rack piston begins to come out of housing. Remove rack piston plug. Insert Rack Piston Arbor (J-21552) into bore of rack piston. Hold tool firmly against worm shaft while turning pinion counterclockwise to force piston from housing. Remove rack piston, rack piston balls and tool from housing.
3. Remove pinion shaft, valve assembly and worm shaft as an assembly. Remove thrust bearing and races. Lightly tap stub shaft on a wood block to loosen shaft cap. Pull out cap and valve spool from valve body approximately 1/4" and disengage stub shaft pin from hole in valve spool. Remove valve spool from valve body. Remove valve spool "O" ring seal, Teflon rings and "O" rings.

Note. DO NOT disassemble valve body. If valve body is defective, replace entire valve body assembly.

Cleaning & Inspection

Clean housing and lubricate all internal components with power steering fluid. Replace steering gear housing if bore is damaged. Replace any worn or damaged components.

Reassembly

1. Lubricate valve spool and "O" ring with power steering fluid. Install valve spool "O" ring seal to valve spool. Install valve spool to valve body until hole in valve spool for pinion shaft pin is accessible from opposite end of valve body.
2. Install pinion shaft to valve spool and insert retaining pin. Ensure notch in pinion shaft cap fully engages valve body pin and seats against valve body shoulder. Lubricate "O" ring seals and teflon rings with power steering fluid and install on valve body. Install thrust bearing and races to worm shaft. Install pinion shaft and valve assembly to worm shaft. Ensure pin on worm shaft aligns with slot in valve assembly. Install pinion shaft, valve assembly and worm shaft into housing.
3. Using Adjuster Plug Bearing Remover and Installer (J-6221), install needle bearing in adjuster plug. Ensure identification mark on needle bearing faces tool during installation. Using same tool, install lip seal and dust seal. Install "O" ring seal, large bearing race, thrust bearing, small bearing race and bearing spacer to adjuster plug. Install thrust bearing retainer to adjuster plug. Install adjuster plug, using care not to cut seals.
4. Install worm shaft to rack piston. Align worm shaft groove with rack piston ball return guide hole. Alternately install Black and Silver balls into rack piston and ball guide while turning worm shaft counterclockwise. Use grease to retain balls in place and install ball guide to rack piston. Install ball guide clamp and screws.
5. Insert Rack Piston Arbor (J-21552) into bore while turning rack piston counterclockwise. Rack piston will be forced onto tool and will hold balls in place. Using same arbor, install rack piston to worm shaft, using Ring Compressor (J-8947) to compress seals. Hold arbor against worm shaft and turn pinion shaft clockwise until rack piston is seated on worm shaft. Install rack piston plug and housing end plug seal, plug and retaining ring. Ensure open end of retaining ring is approximately 1" (25 mm) from housing access hole.
6. DO NOT remove arbor until valve body piston ring has entered housing bore. Turn pinion shaft until rack piston center groove is aligned with center of pitman shaft bearing bore. Lubricate side cover gasket and install on side cover. Thread cover onto adjusting screw until cover bottoms against pitman shaft.
7. Install pitman shaft so long center sector tooth meshes with rack piston center groove. Install side cover and gasket on housing. Install and tighten side cover bolts to 45 ft. lbs. (61 N.m). Thread adjuster screw lock nut halfway on adjuster screw. Prevent screw from turning with Allen wrench while installing nut. Adjust steering gear. See «ADJUSTMENTS»(/cadillac/brougham/i-1987-1992/remont/manual-power-steering/#steering-gear-power-rwd) in this article.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• TROUBLE SHOOTING - BASIC PROCEDURES
• POWER STEERING GENERAL SERVICING
• ADJUSTMENTS