Steering System Land Rover Discovery L318

(Scheme 1)

Scheme 1

STEERING COLUMN ASSEMBLY & INTERMEDIATE SHAFT

(Scheme 2)

Scheme 2

STEERING BOX

(Scheme 3)

Scheme 3

General

The major steering components comprise an impact absorbing telescopic steering column, a Power Assisted Steering (PAS) box, a PAS pump, and fluid reservoir. Hydraulic fluid from the fluid reservoir is filtered and then supplied through the suction line to the inlet on the PAS pump. The PAS pump supplies fluid to the steering box through a pressure line routed above the front cross member. Fluid returns to the reservoir along the same route through a return line. On left drive vehicles the pipe route above the front cross member is still used, the length of pipe acting as an oil cooler.

To minimize driver's injury in the event of an accident the steering system has a number of safety features including a collapsible steering column. An additional safety feature is an air bag located in the steering wheel.

Steering Column

Assembly and intermediate shaft The steering column central shaft comprises of two shafts, the upper shaft is splined to accept the steering wheel and located in bearings in the column tube. A universal joint is located on the bottom of the upper shaft, the joint allows for angular movement between the upper and lower shafts. The lower shaft is made in two parts, the top section of the lower shaft is located outside of the lower section. The two sections of the lower shaft are connected by two nylon injection molded shear pins. The lower shaft goes through a lower bearing attached to the bulkhead, the lower shaft is connected by a universal joint to the intermediate shaft in the engine compartment.

An upper column tube provides for the location of the steering lock and ignition switch and also the steering switch gear and a rotary coupler. The rotary coupler provides the electrical connection for the steering wheel mounted airbag, switches and horn. The upper mounting bracket has two slots, a slotted metal bracket is held in each slot by four resin shear pins.

The column is mounted on four captive studs which are located on a column mounting bracket. The captive studs pass through the metal brackets, locknuts secure the steering column to the bulkhead. The two lower mountings are fixed and cannot move when loads are applied to them. The upper mounting is designed to disengage or deform when a load is applied, allowing the column to collapse in the event of an accident. The steering column must be replaced as a complete assembly if necessary.

When an axial load is applied to the upper column tube, energy absorption is achieved by the following mechanism

1. The mounting bracket deforms.
2. The resin shear pins holding the slotted metal brackets shear.
3. The top mounting bracket slides out of the slotted metal brackets.

The slotted metal brackets remain on the captive studs on the bulkhead. If the column mounting moves, injection molded shear pins retaining the two sections of the lower column shaft will shear. This allows the two sections of the lower shaft to "telescope" together.

In the event of a collision where the steering box itself moves, two universal joints in the column allow the intermediate shaft to articulate, minimizing movement of the column towards the driver. If movement continues energy absorption is achieved by the following mechanism

1. The de-couple joint in the intermediate shaft will disengage.
2. The lower section of the steering column shaft will move through the lower bearing.
3. The injection molded shear pins retaining the two sections of the lower column shaft will shear.

This allows the two sections of the lower shaft to "telescope" together reducing further column intrusion. Protection to the drivers face and upper torso is provided by an SRS airbag module located in the center of the steering wheel.

Tilt Adjustment

The column tilt adjuster lever mechanism is located on the left side of the steering column and allows the upper column tube, nacelle and steering wheel assemblies to be tilted up or down a maximum of 7.5° or 47 mm (NAS vehicles have a smaller range of movement than the ROW vehicles).

The pawl of the mechanism is attached to the lower column and is allowed to pivot, a toothed quadrant is fixed to the upper column tube.

When the lever on the left side of the steering column is raised the mechanism releases the pawl from the toothed quadrant, this allows the column to be moved. When the lever is released two return springs pull the pawl into engagement with the toothed quadrant.

Steering Column Lock (All Except NAS)

The steering column lock houses the ignition switch, ignition illumination light ring, key lock barrel and the alarm passive coil. The steering lock is attached to the upper column with two shear bolts. The bolts are tightened to a torque which shears off the heads of the bolts preventing easy removal of the steering lock.

The steering lock operates by a bolt, which emerges when the ignition key is turned to position "0" and the ignition key removed. The bolt engages in a lock collar located on the upper shaft in the upper column tube. The lock collar is attached to the upper shaft by a WAVE FORM interference ring. If a high torque is applied via the steering wheel with the lock engaged, the lock collar will slip on the upper shaft. This prevents damage to the steering lock, yet still prevents the vehicle from being driven.

Steering Column Lock (NAS Only)

The steering column lock houses the ignition switch, ignition illumination light ring, key lock barrel and the alarm passive coil. The steering lock is attached to the upper column with two shear bolts. The bolts are tightened to a torque which shears off the heads of the bolts preventing easy removal of the steering lock.

The steering column lock operates by a bolt, which emerges when the ignition key is turned to position "0" and the ignition key removed. The bolt engages in a groove machined into the upper shaft in the column tube.

Steering Wheel

The steering wheel comprises a cast center and wire frame onto which the soft polyurethane foam is molded. The steering wheel is located on the upper column shaft by a spline and is secured with a nut. A remote radio control switch (if fitted) is located on the left side of the steering wheel, a cruise control switch may be located on the right side. Horn switches are located on each side of the center of the steering wheel and protrude through the airbag module cover. Both switches are connected by wires to the rotary coupler connector.

Intermediate Shaft

One end of the intermediate shaft is attached to the steering column lower shaft by a splined universal joint and a bolt, the universal joint is part of a rubber coupling assembly. The rubber coupling assembly is covered by a heat shield and connects to the lower section of the intermediate shaft via a de-couple joint. The rubber coupling reduces the shocks felt by the driver through the steering wheel. A second universal joint on the other end of the intermediate shaft is held in by a bolt. The universal joint is splined and engages with the splined rotor (input) shaft of the steering box.

The de-couple joint consists of a metal plate that has open ended slots, the plate is bolted through the slots into the other half of the de-couple joint. The top half of the de-couple joint has a slot that accepts the lower section of the intermediate shaft. The slotted metal plate clamps the lower section of the intermediate shaft to the top section. An indicator clip is installed between the slotted metal plate and the top half of the de-couple joint.

If the intermediate shaft is compressed in an accident, the slotted metal plate in the de-couple joint will disengage if sufficient force is applied to the front end of the shaft. If the forces involved do not disengage the shaft, the red indicator clip located in the de-couple joint will break off if the shaft moves. The intermediate shaft cannot be repaired and must be replaced as an assembly if accident damage occurs.

Reservoir

The fluid reservoir is made of molded plastic and is located on left side of the engine compartment, on a bracket which is attached to the inner wing. Dependent on the vehicles specification the reservoir may be a dual Power Assisted Steering (PAS)/Active Cornering Enhancement (ACE), or PAS only reservoir. Both types of reservoir are similar to each other the dual PAS/ACE reservoir has two chambers, the PAS only reservoir has one chamber of a larger capacity. On both types of reservoir the PAS chamber has its own filler cap and is identified by lettering on the reservoir body.

A filter of fine polyester mesh is molded into the base of the chamber. The filter removes particulate matter from the fluid before it is drawn into the supply connection and is non-serviceable. Upper and lower level marks are molded into the reservoir body, the reservoir is fitted with filler cap, a seal in the cap prevents leakage. The filler cap is pushed onto a latch and turned through 90° to lock. A breather hole is incorporated in the cap to allow venting of air due to fluid level changes during operation. The breather hole also allows air that may be in the fluid to separate out and vent to atmosphere.

The reservoir holds hydraulic fluid and allows for expansion and contraction of the fluid due to temperature variations. With the reservoir correctly filled the inlet to the PAS pump will be kept covered at normal operational attitudes. The fluid flowing to the reservoir is cooled by convection from the pipe surfaces, the fluid held in the reservoir also allows convection from the sides of the reservoir to take place. The total capacity of the reservoir with PAS only is 1000 cc (0.264 US gallons), for vehicles fitted with PAS and ACE the total capacity of the reservoir is 500 cc (0.132 US gallons).

Scheme 4

The steering box is located behind the first cross member of the chassis and is secured to the chassis rail with four bolts. (Scheme 5) The steering box is of the worm and roller type and has a rotary control valve. The steering box is connected to the steering knuckles of the front road wheels by the drop arm, drag link and track rod. The steering box is lubricated by the hydraulic fluid in the housing. The input shaft is attached to the steering wheel via the intermediate shaft and steering column. The drop arm is secured to the output shaft with a nut and tab washer. A ball joint allows movement between drop arm and drag link, the ball joint is secured with a locknut. The steering box requires approximately 3.5 turns from lock to lock.

As a maintenance aid, an alignment bolt can be used to lock the drop arm at the steering box center position. The bolt fits in a groove in the rear face of the drop arm and screws in to a threaded hole on the bottom of the steering box housing.

Scheme 5

Principle Of Operation

Movement of the input shaft is transferred through the pin to the torsion bar and valve rotor on the input shaft. As the input shaft turns, the spline of the torsion bar turns the worm gear. This action causes the roller to rotate on its bearings and move. As the roller is located by a pin to a yoke on the output shaft, the output shaft rotates in the steering box housing. As the amount of torque acting on the input shaft increases the torsion bar starts to twist. As the torsion bar twists the valve rotor turns in the valve sleeve. When the ports in the valve rotor and valve sleeve are turned, hydraulic fluid is directed to chamber "A" or "B" in the power cylinder.

With hydraulic fluid in one chamber under high pressure, the piston moves. The return line ports in the rotary valve, aligned by the movement of the valve rotor, allow the fluid in the opposite chamber to flow to return. The teeth of the rack move and transfer the force from the piston to the output shaft, giving assistance to move the drop arm. As the output shaft rotates the torsion bar load is decreased. The rotor on the input shaft will return as the torsion bar unwinds, the rotary valve will then be in a neutral position and the pressure in chambers "A" and "B" will equalize. With no high pressure acting on the piston, force on the piston and rack is released.

To prevent heat accumulation at full steering lock due to excessive pressure, a relief valve inside the steering box is opened as the box approaches full lock. The relief valve pins are located in the cylinder cover and housing and are not to be adjusted.

The steering box design ensures a mechanical link through the course spline on the control valve rotor, the spline will become engaged if

1. The hydraulic pressure fails.
2. The steering box rotary control valve fails.

The coarse spline may also engage in some full lock situations if sufficient torque is applied to the input shaft.

Rotary Control Valve

The rotary valve assembly comprises of three parts. (Scheme 6) The valve sleeve is fixed inside one end of the worm gear, the valve sleeve has ports through it to allow the passage of hydraulic fluid. The input shaft has a valve rotor machined on one end, the valve rotor also has ports through it and can rotate in the valve sleeve. A torsion bar is attached to the input shaft by a pin, the torsion bar goes through the input shaft and valve rotor and is engaged by a spline into the worm gear.

The coarse spline on the end of the valve rotor is loosely engaged in the worm gear, the coarse spline can make contact and drive the worm gear in some full lock and in no pressure conditions. In the event of a torsion bar failure, power assistance will be lost, the coarse spline will drive the worm gear and enable the vehicle to be steered and driver control maintained.

When there is no demand for assistance the torsion bar holds the ports in the valve sleeve and valve rotor in a neutral relationship to one another. The ports in the valve sleeve and the valve rotor are so aligned to allow equal (low) fluid pressure on each side of the piston. Excess fluid flows through ports in the valve rotor through the valve sleeve and back to the reservoir.

Scheme 6

Rotary Control Valve In Demand Mode

When the steering wheel and input shaft is turned steering resistance transmitted to the worm causes the torsion bar to be wound up and the valve ports in the valve rotor and valve sleeve to be aligned for a right or left turn. The alignment of the valve ports directs fluid pressure "A" from the Power Assisted Steering (PAS) pump to one side of the piston/rack. The other side of the piston/rack is now connected to return "B" (due the valves port alignment) and displaced fluid returns to the reservoir. The pressure difference in the cylinder on each side of the piston gives the power assistance to move the rack and so turn the steering.

The greater the resistance of the road wheels to the steering rotary movement, the greater torque acting on the torsion bar and input shaft causing greater changes of alignment of the ports in the valve. As the change of alignment becomes greater, the fluid pressure passing to the applicable side of the piston/rack increases. (Scheme 7)

Only when the steering wheel stops turning and the torsion bar has unwound, will the valve rotor return to the neutral position. In the neutral position the fluid circulates through the ports in the valve rotor and valve sleeve and back to the reservoir where it is cooled.

Scheme 7

Power Assisted Steering (PAS) Pump - V8

The Power Assisted Steering (PAS) pump is located on the auxiliary housing and is attached by two bolts, the bolts go through flanged bushes in the auxiliary housing. (Scheme 8) A stud passes through the PAS pump and through a flanged bush in the auxiliary housing, the auxiliary housing and PAS pump are secured by a nut. As the two bolts and nut are tightened the bushes move slightly and the flange of each bush clamps the PAS pump. A drive pulley is attached to the pump drive shaft with three bolts, and is belt driven at a ratio of 1.4 crankshaft revolutions to 1 of the drive pulley. Fluid is drawn into the PAS pump inlet from the reservoir through a flexible hose at low (suction) pressure. Fluid at high pressure from the PAS pump outlet is supplied to the rotary control valve on the steering box.

The PAS pump is a roller vane type and has an internal pressure regulator and flow control valve. The roller vanes can move in slots in the pumps rotor and are moved outwards by centrifugal force as the pump rotates. The pump rotor rotates in the pump housing, the internal shape of the housing forms a CAM shape. Due to the CAM shape the volume of the housing decreases between the inlet and outlet ports.

As the pump rotor rotates towards the pump inlet the volume between the roller vanes and the pump housing increases, this action causes a depression in the chamber between the pump roller vanes and the housing. As the rotation continues the chamber is opened to the pump inlet, and the depression in the chamber causes fluid to be drawn in. The roller vanes continue past the inlet port, closing off the inlet port and trapping the fluid in the chamber between the rollers and the pump housing.

The internal CAM shape of the pump housing causes the rollers to move closer together as the pump rotor rotates towards the outlet port. The reduced volume of the chamber between the roller vanes causes the fluid to become pressurized. When the chamber is opened to the outlet port of the pump the fluid escapes at high pressure. The roller vanes continue turning and go past the outlet port, closing off the chamber between the two roller vanes.

As rotation continues the inlet sequence begins again. The inlet and pressurization/outlet sequences continue as the pump rotates, and is repeated between each two roller vanes. The pump is a positive displacement type and the potential pump output increases with engine (drive pulley) speed. The pressure relief and flow control valve regulates flow/pressure by diverting fluid back to the pump inlet through internal recirculation passages in the pump body.

Scheme 8

Steering Damper

The steering damper is located behind and just below the first cross member of the chassis. The ends of the steering damper have steel EYES welded on, rubber bushes are installed in each EYE. The steering damper is attached between brackets on the chassis rail and the drag link. Each end of the steering damper is secured by a bolt and locknut. The hydraulic damper absorbs shocks in the steering, caused by road wheel deflections when operating on rough terrain.

OPERATION

Hydraulic fluid is supplied to the Power Assisted Steering (PAS) pump inlet from the PAS reservoir, the PAS pump draws in and pressurizes the fluid. The PAS pump self regulates internal flow rates and operating pressure, and supplies pressurized fluid from the PAS pump outlet to a rotary control valve in the steering box. At neutral the fluid is circulated by the PAS pump and flows around the system at a lower pressure and a constant flow rate. With most of the fluid being returned to the reservoir the pressure inside the system remains very low. When a control input turns the rotary control valve in the steering box, pressure in the system will rise as the control valve directs fluid to give power assistance.

The action of turning the steering wheel turns the steering column and intermediate shaft. The intermediate shaft turns the input shaft of the steering box. The input shaft moves the rotary control valve in the steering box, the rotary valve controls the pressure used inside the steering box for power assistance. The input shaft also turns a worm gear, the worm gear acts on a roller attached to the output shaft. As the worm gear turns the roller, the roller travels along the lands of the worm gear. As the roller is attached to the output shaft the output shaft turns.

As the output shaft of the steering box turns, hydraulic pressure is supplied via the rotary control valve to the steering box. The hydraulic pressure acts on a rack that assists with the movement of the output shaft of the steering box. A drop arm is attached to the output shaft of the steering box. The drop arm is connected to a drag link by a ball joint. The drag link is connected via ball joints to one front steering knuckle and road wheel. A track rod connected to this steering knuckle links the two steering knuckles together. As one steering knuckle and road wheel is turned by the drag link, the other steering knuckle and wheel is moved by the track rod.

Check

1. Raise front of vehicle.
2. Remove nut securing drag link to drop arm.
3. Using LRT-57-036, break taper joint and release drag link. (Scheme 9)
4. Ensure steering is centralized.
5. With the drop arm held, check for rotational movement at the intermediate shaft universal joint. If any movement exists, the steering box requires adjusting.

Scheme 9

Adjust

1. Loosen lock nut on steering box adjuster and tighten adjuster until movement is removed at universal joint. (Scheme 10)
2. When adjustment is correct, hold the adjuster and tighten adjuster locknut.
3. Turn steering wheel from lock to lock and check no tightness exists.
4. Fit drag link to drop arm, and tighten nut to 80 Nm (59 ft. lbs.).
5. Remove stands and lower vehicle.

Scheme 10

Bleed

1. Clean Power Assisted Steering (PAS) fluid reservoir around filler cap and fluid level indicators.
2. Remove filler cap from PAS fluid reservoir. If necessary, fill PAS fluid reservoir to upper level indicator with recommended fluid. See «CHECK/TOP-UP -- PAS/ACE RESERVOIRS»(/land-rover/discovery/l318-2002-2004/remont/procedures/#maintenance).
3. Start engine and run to normal operating temperature.
4. Position container to catch fluid spillage from steering box.
5. With engine at idle speed, and an assistant turning the steering from lock to lock, loosen bleed screw on top of steering box. Keep PAS fluid reservoir topped up and allow all air to bleed from system. When fluid from bleed screw is free of air, tighten bleed screw. (Scheme 11)
6. Stop engine.
7. Clean spilled PAS fluid from steering box and surrounding area.
8. Check fluid level in PAS fluid reservoir and fill to upper level mark. If fluid is aerated, wait until fluid is free from bubbles.
9. Fit PAS fluid reservoir filler cap.

Scheme 11

STEERING LINKAGE - CENTRALIZE

The following procedure assumes that the front wheel alignment is correctly adjusted.

1. Raise front of vehicle, and position the road wheels at straight ahead.
2. Remove nut securing drag link to drop arm. Using tool LRT-57-036 break taper joint and release drag link from drop arm. (Scheme 12)
3. Fit centralizing bolt to steering box and ensure that front road wheels are in the straight ahead position. (Scheme 13)
4. Loosen clamp bolts on drag link.
5. Adjust drag link so that taper joint is centralized in drop arm, then tighten drag link clamp bolts: Tighten M8 bolts to 22 Nm (16 ft. lbs.) and M10 bolts to 33 Nm (24 ft. lbs.).
6. Connect drag link to drop arm and tighten nut to 80 Nm (59 ft. lbs.).
7. Remove steering box centralizing bolt.
8. Remove stand(s) and lower vehicle.
9. Road test the vehicle and check that the steering wheel is centralized. If steering wheel is not centralized, proceed as follows.
10. Slacken drag link adjuster clamp bolts. (Scheme 14)
11. Without disconnecting drag link from drop arm, adjust the length of the drag link to bring the steering wheel to the central position.
12. Tighten drag link clamp bolts: Tighten M8 bolts to 22 Nm (16 ft. lbs.) and M10 bolts to 33 Nm (24 ft. lbs.)

Scheme 12

Scheme 13

Scheme 14

WHEEL ALIGNMENT - FRONT

For wheel alignment procedures

1. For 1999 models, see «SPECIFICATIONS & PROCEDURES»(ref-5224) article.
2. For 2000 models, see «SPECIFICATIONS & PROCEDURES»(ref-5224) article.
3. For 2001 models, see «SPECIFICATIONS & PROCEDURES»(/land-rover/discovery/l318-2002-2004/remont/wheel-alignment/#wheel-alignment-specifications-procedures) article.
4. For 2002 models, see «SPECIFICATIONS & PROCEDURES»(/land-rover/discovery/l318-2002-2004/remont/wheel-alignment/#wheel-alignment-specifications-procedures) article.
5. For 2003 models, see «SPECIFICATIONS & PROCEDURES»(/land-rover/discovery/l318-2002-2004/remont/wheel-alignment/#wheel-alignment-specifications-procedures) article.
6. For 2004 models, see «SPECIFICATIONS & PROCEDURES»(/land-rover/discovery/l318-2002-2004/remont/wheel-alignment/#wheel-alignment-specifications-procedures) article.

1. Disconnect battery earth lead.
2. Siphon Power Assisted Steering (PAS) fluid from reservoir.
3. Raise front of vehicle and support on stands.
4. Turn steering on left lock.
5. Remove 3 screws securing left splash shield and remove shield. (Scheme 15)
6. Release clip securing PAS pipes. (Scheme 16)
7. Position absorbent cloth to catch spillage.
8. Position container to collect PAS fluid spillage.
9. Release clips and remove air intake hose from air cleaner housing. (Scheme 17)
10. Discard intake "O" ring and move intake aside for access.
11. Loosen union securing high pressure pipe to PAS pump and release pipe. (Scheme 18)
12. Fit adaptor LRT-57-034A to high pressure port of PAS pump. (Scheme 19)
13. Fit adaptor LRT-57-035 to existing high pressure hose.
14. Fit hose LRT-57-002/3 to each adaptor.
15. Fit pressure gauge LRT-57-005 to test valve LRT-57-001
16. Connect hoses LRT-57-002/3 to LRT-57-001 and tighten unions.
17. Hang pressure gauge in a safe position under bonnet.
18. Remove PAS reservoir filler cap, fill to level indicator and refit cap.
19. Connect battery earth lead.
20. Start engine and allow air to bleed from PAS system by turning steering from lock to lock. Stop engine and check PAS fluid level.
21. Ensure steering system and test equipment are free from leaks.
22. Maintain maximum fluid level during test.
23. Open the test valve on LRT-57-001 and start the engine.
24. With the engine at idle, slowly turn the steering wheel and hold on full lock.
25. Note the pressure reading on LRT-57-005.
26. Repeat the pressure check for the opposite full lock.
27. Test pressure should be between 21 and 62 bar, (300 to 900) psi. Dependent on road surface.
28. With the engine at idle, centralize the steering wheel. Pressure should read 7 bar (100 psi) or below.
29. Pressures outside the above tolerance indicates a fault.
30. To determine if fault is in steering pump or steering box, close the valve on LRT-57-001 for a maximum of 5 seconds. Pump damage may occur if test valve is closed for longer periods.
31. If gauge does not register between 75 and 103 bar, (1500 psi), (maximum pump pressure), the pump is faulty.
32. If maximum pump pressure is correct suspect the steering box.
33. On completion stop engine, disconnect battery earth lead and siphon fluid from PAS reservoir.
34. Remove test equipment from LRT-57-002.
35. Clean PAS pump and pipe union.
36. Fit new "O" ring to high pressure pipe, align to PAS pump and tighten union to 25 Nm (18 ft. lbs.).
37. Secure PAS pipes in clip.
38. Using new "O" ring fit intake hose to air cleaner and secure clips.
39. Remove PAS reservoir filler cap, fill to level indicator and refit cap.
40. Connect battery earth lead.
41. Start engine and allow air to bleed from PAS system, by turning steering from lock to lock.
42. Visually check PAS system for leaks.
43. Clean chassis member.
44. Check power steering fluid, if aerated, wait until fluid is free from bubbles then top-up reservoir to UPPER level mark.
45. Lower vehicle.
46. Dismantle test equipment.

Scheme 15

Scheme 16

Scheme 17

Scheme 18

Scheme 19

Removal

1. Raise front of vehicle.
2. Remove front road wheel.
3. Ensure steering wheel is centralized and fit centralizing bolt to steering box. Remove key from steering lock and engage column lock. (Scheme 20)
4. Remove 3 bolts securing intermediate shaft and universal joint. (Scheme 21)
5. Push intermediate shaft upwards, release and remove universal joint.
6. Position container to catch oil spillage.
7. Right drive models: Remove 4 bolts securing oil filter housing, remove housing and discard "O" ring. (Scheme 22)
8. Remove bolt securing PAS pipe bracket to steering box, release pipes and discard "O" rings. (Scheme 23)
9. Remove securing nut and bolt and release Panhard rod. (Scheme 24)
10. Remove nut securing drag link to drop arm. Using LRT-57-036, break taper joint and release drag link. (Scheme 9)
11. Right drive models with Active Cornering Enhancement (ACE): Remove nut securing anti-roll bar link lower ball joint and release joint. (Scheme 25)
12. Right drive models with ACE: Position ACE control arms to access steering box bolts. (Scheme 26)
13. With assistance remove 4 securing bolts and remove steering box.
14. Remove centralizing bolt from steering box.

Scheme 20

Scheme 21

Scheme 22

Scheme 23

Scheme 24

Scheme 25

Scheme 26

Installation

1. Fit centralizing bolt to steering box.
2. With assistance, position steering box, fit bolts and tighten to 90 Nm (66 ft. lbs.).
3. Right drive models with Active Cornering Enhancement (ACE): Ensure washer is in place on lower ball joint of anti-roll bar link, then connect lower ball joint to axle. Tighten nut to 100 Nm (74 ft. lbs.).
4. Position drag link, fit nut and tighten to 80 Nm (59 ft. lbs.).
5. Position Panhard rod, fit bolt and nut and tighten to 230 Nm (170 ft. lbs.).
6. Clean Power Assisted Steering (PAS) pipe ends and "O" ring recess.
7. Lubricate new "O" rings for PAS pipes with clean PAS fluid.
8. Fit "O" rings to PAS pipes and position pipes in steering box. Fit PAS pipe bracket and tighten bolt to 22 Nm (16 ft. lbs.).
9. Right hand drive models: Fit oil filter and housing: Clean oil filter housing and engine mating faces. Lubricate new "O" ring with clean engine oil and fit to housing. Position oil filter housing and tighten bolts to 9 Nm (7 ft. lbs.).
10. Ensure steering wheel is centralized. Fit universal joint between steering box and intermediate shaft and tighten bolts to 25 Nm (18 ft. lbs.).
11. Remove centralizing bolt from steering box.
12. Fit road wheel(s) and tighten nuts to 140 Nm (103 ft. lbs.).
13. Remove stand(s) and lower vehicle.
14. Check and top up engine oil.
15. Bleed PAS system. See «HYDRAULIC SYSTEM - BLEED»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system) .
16. Centralize steering linkage. See «STEERING LINKAGE - CENTRALIZE»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system__steering-linkage-centralize) .

1. Remove steering box for V8 models. See «POWER STEERING BOX - V8»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system).
2. Secure steering box in vice.
3. Remove circlip and extract oil seal from steering box. Take care not to damage surface of the shaft. (Scheme 27)

Scheme 27

1. Clean oil seal recess and input shaft.
2. Lubricate new seal with clean Power Assisted Steering (PAS) fluid.
3. Fit seal using LRT-57-503.
4. Fit circlip.
5. Fit steering box for V8 models. See «POWER STEERING BOX - V8»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system) .

1. Remove steering box for V8 models. See «POWER STEERING BOX - V8»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system).
2. Secure steering box in vice.
3. Release lock washer from drop arm nut.
4. Loosen but do not remove nut securing drop arm.
5. Using LRT-57-012, release drop arm. (Scheme 28)
6. Remove nut and discard lock washer.
7. Remove drop arm.
8. Mark position of rack adjuster. (Scheme 29)
9. Remove Allen screw securing rack adjuster and loosen adjuster one turn.
10. Remove 4 bolts securing output shaft assembly and remove output shaft assembly. Remove and discard "O" ring from end cover.
11. Remove seal shield and circlip. (Scheme 30)
12. Remove seal and spacer.

Scheme 28

Scheme 29

Scheme 30

1. Clean seal recess, output shaft, end cover and mating face.
2. Lubricate new end cover "O" ring with clean Power Assisted Steering (PAS) fluid. Fit "O" ring to end cover.
3. Position output shaft, fit bolts and tighten to 88 Nm (65 ft. lbs.).
4. Tighten rack adjuster one turn, align marks and secure with Allen screw.
5. Lubricate new output shaft seal with clean PAS fluid.
6. Fit seal using LRT-57-504.
7. Fit spacer, circlip and seal shield.
8. Clean drop arm and steering box splines.
9. Ensure steering box is in the central position. Align and fit drop arm to output shaft and secure with new lock washer and nut. Tighten nut to 240 Nm (177 ft. lbs.).
10. Secure lock washer to drop arm nut.
11. Fit steering box for V8 model. See «POWER STEERING BOX - V8»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system) .

1. Remove auxiliary drive belt. See «ACCESSORY DRIVE BELT (DISCOVERY II)»(/land-rover/discovery/l318-2002-2004/remont/charging-system/#generators-regulators).
2. Remove cable tie securing harness to air intake hose.
3. Loosen 3 clips securing air intake hose, release and remove hose. (Scheme 31)
4. Models with Active Cornering Enhancement (ACE): Remove 3 bolts securing ACE pump, release pump and position aside. (Scheme 32)
5. Models with A/C: Disconnect A/C compressor multiplug. Remove 4 bolts securing A/C compressor, release compressor and position aside. (Scheme 33)
6. Remove 3 bolts securing Power Assisted Steering (PAS) pump pulley and remove pulley. (Scheme 34)
7. Position tray to catch spillage, release PAS pump pressure pipe.
8. Remove clip and release PAS pump inlet hose.
9. Remove jockey pulley. (Scheme 35)
10. Remove bolt securing oil cooling pipe bracket and release bracket from housing. (Scheme 36)
11. Remove two bolts securing PAS pump.
12. Remove 4 bolts and one nut securing auxiliary housing. Pull housing forward and release PAS pump. Remove PAS pump.

Scheme 31

Scheme 32

Scheme 33

Scheme 34

Scheme 35

Scheme 36

1. Position Power Assisted Steering (PAS) pump to auxiliary housing and locate housing to engine. Fit and tighten auxiliary housing bolts to 40 Nm (30 ft. lbs.).
2. Tighten auxiliary housing nut to 10 Nm (7 ft. lbs.).
3. Fit bolts securing PAS pump and tighten to 22 Nm (16 ft. lbs.).
4. Position PAS pump pipe bracket, fit and tighten bolt to 22 Nm (16 ft. lbs.).
5. Fit and tighten PAS pump pressure pipe.
6. Fit PAS pump inlet hose and secure with clip.
7. Position jockey pulley and tighten bolt to 50 Nm (37 ft. lbs.).
8. Clean PAS pump pulley mating faces.
9. Position PAS pump pulley, fit bolts and tighten to 22 Nm (16 ft. lbs.).
10. Models with Active Cornering Enhancement (ACE): Clean ACE pump dowels and dowel holes. Position ACE pump, fit bolts and tighten to 25 Nm (18 ft. lbs.).
11. Models with A/C: Clean A/C compressor dowels and dowel holes. Position A/C compressor, fit bolts and tighten to 22 Nm (16 ft. lbs.).
12. Position air intake hose and secure with clips.
13. Secure harness to air intake hose with new cable tie.
14. Fit auxiliary drive belt. See «ACCESSORY DRIVE BELT (DISCOVERY II)»(/land-rover/discovery/l318-2002-2004/remont/charging-system/#generators-regulators) .

1. Remove steering column intermediate shaft. See «SHAFT - INTERMEDIATE & UNIVERSAL JOINT - STEERING COLUMN»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system__shaft-intermediate-universal-joint).
2. Remove rotary coupler: For 1999 models, see «ROTARY COUPLER»(ref-98367-S21327188712001052200000). For 2000 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-97309-S24893648402001043000000). For 2001 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-150004-S40472838732002110400000). For 2002 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-150779-S03980545112002112100000). For 2003 models, see «ROTARY COUPLER (CLOCKSPRING)»(/land-rover/discovery/l318-2002-2004/remont/airbag/#air-bag-restraint-systems). For 2004 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-170459-S01055400812005011000000).
3. Open fascia lower access panel.
4. Remove steering column nacelle. See «NACELLE - STEERING COLUMN»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system).
5. Disconnect multiplug and illumination bulb from passive coil and remove passive coil. (Scheme 37)
6. Disconnect 2 multiplugs from wiper switch assembly. (Scheme 38)
7. Disconnect 2 multiplugs from light switch assembly.
8. Loosen screw and remove switch assembly. (Scheme 39)
9. Disconnect ignition switch multiplug.
10. Disconnect multiplug from ignition switch housing. (Scheme 40)
11. Release harness from column clip. (Scheme 41)
12. Remove 4 nuts securing steering column assembly to fascia rail and remove steering column assembly.
13. Remove rubber boot from steering column assembly. (Scheme 42)
14. Position steering column assembly in a vice. (Scheme 43)
15. Remove 2 screws and remove ignition switch.
16. Remove cable tie and remove multiplug from ignition switch.
17. Centre punch or drill out steering lock shear bolts.
18. Remove steering lock.

Scheme 37

Scheme 38

Scheme 39

Scheme 40

Scheme 41

Scheme 42

Scheme 43

1. Position lock to steering column assembly and fit shear bolts. Do not tighten shear bolts at this stage.
2. Insert starter key, check operation of steering lock and that key turns freely.
3. Tighten shear bolts fully and shear heads off.
4. Position ignition switch to column, fit and tighten screws.
5. Position multiplug to switch and secure with new cable tie.
6. Fit rubber boot to column.
7. Remove column from vice.
8. Position steering to fascia rail fit nuts and tighten to 22 Nm (16 ft. lbs.).
9. Secure harness to column clip.
10. Position rubber grommet.
11. Close access panel and secure turn buckles.
12. Connect ignition switch multiplugs.
13. Position column switch and tighten clamp screw.
14. Connect column switch multiplugs.
15. Position passive coil, connect multiplug and illumination bulb.
16. Fit steering column nacelle. See «NACELLE - STEERING COLUMN»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system) .
17. Fit rotary coupler: For 1999 models, see «ROTARY COUPLER»(ref-98367-S21327188712001052200000) . For 2000 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-97309-S24893648402001043000000) . For 2001 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-150004-S40472838732002110400000) . For 2002 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-150779-S03980545112002112100000) . For 2003 models, see «ROTARY COUPLER (CLOCKSPRING)»(/land-rover/discovery/l318-2002-2004/remont/airbag/#air-bag-restraint-systems) . For 2004 models, see «ROTARY COUPLER (CLOCKSPRING)»(ref-170459-S01055400812005011000000) .
18. Close fascia lower access panel.
19. Fit steering column intermediate shaft. See «SHAFT - INTERMEDIATE & UNIVERSAL JOINT - STEERING COLUMN»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system__shaft-intermediate-universal-joint) .

SHAFT - INTERMEDIATE & UNIVERSAL JOINT - STEERING COLUMN

The intermediate shaft has a red indicator clip fitted which must be inspected at service, and after the vehicle has been subject to an impact. If the clip is not present or is not fully seated against the clamp plate, a new assembly must be fitted.

1. Left hand drive diesel: Loosen 2 clips securing intercooler to turbocharger hose. Place hose aside. (Scheme 44)
2. Remove bolt securing intermediate shaft to steering column. (Scheme 45)
3. Remove bolt securing intermediate shaft to universal joint.
4. Universal joint: Remove the bolt securing the universal joint to the steering box.
5. Ensure steering wheel is in the straight ahead position and fit centralizing bolt to steering box. Remove the key from the ignition switch. (Scheme 46)
6. Intermediate shaft: Slide the intermediate shaft upwards, release from the universal joint and remove intermediate shaft from the steering column. (Scheme 47)
7. Universal joint: Slide the intermediate shaft upwards, release from the universal joint and remove universal joint from the steering box.

Scheme 44

Scheme 45

Scheme 46

Scheme 47

1. Clean and inspect splines for wear and damage.
2. Intermediate shaft: Locate intermediate shaft on steering column and engage with universal joint. Ensure splines are fully engaged and bolt holes aligned.
3. Universal joint: Locate universal joint on steering box and engage in intermediate shaft. Ensure splines are fully engaged and bolt holes aligned.
4. Fit bolts securing intermediate shaft to universal joint and tighten to 25 Nm (18 ft. lbs.).
5. Intermediate shaft: Fit bolts securing intermediate shaft to steering column and tighten to 25 Nm (18 ft. lbs.).
6. Universal joint: Fit bolts securing universal joint to steering box and tighten to 25 Nm (18 ft. lbs.).
7. Left hand drive diesel: Connect hose to turbocharger and intercooler and secure the clips.
8. Fit ignition key, remove steering box centralizing bolt and check that steering wheel is in the straight ahead position.

1. Open fascia lower access panel.
2. Remove 3 screws securing steering column nacelle halves together. (Scheme 48)
3. Release clips securing nacelle together and remove from steering column.

Scheme 48

1. Position nacelle to steering column and secure with clips and screws.
2. Close fascia lower access panel.

1. Remove steering box for V8 models. See «POWER STEERING BOX - V8»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system).
2. Secure steering box in vice. (Scheme 28)
3. Release drop arm nut lock washer.
4. Loosen but do not remove nut securing drop arm.
5. Using LRT-57-012 release drop arm.
6. Remove nut and lock washer.
7. Remove drop arm.

1. Clean drop arm and steering box splines.
2. Ensure steering box is in the central position. Align and fit drop arm to output shaft and secure with lock washer and nut. Tighten nut to 240 Nm (177 ft. lbs.).
3. Secure lock washer to drop arm nut.
4. Fit steering box for V8 models. See «POWER STEERING BOX - V8»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system) .

1. Raise front of vehicle.
2. Remove left front road wheel.
3. Loosen adjuster clamp bolts. (Scheme 49)
4. Remove nut securing track rod ball joint to steering knuckle.
5. Using tool LRT-57-036 break taper joint and release track rod.
6. Unscrew ball joint and adjuster. (Scheme 50)
7. Remove clamps from adjuster and track rod.

Scheme 49

Scheme 50

1. Clean adjuster, clamps and track rod.
2. Fit clamps to track rod and adjuster. Screw in adjuster and ball joint.
3. Clean ball joint taper and taper seat.
4. Adjust length of track rod so that ball joint taper is centralized in steering knuckle.
5. Fit track rod to steering knuckle and tighten nut to 80 Nm (59 INCH lbs.).
6. Fit road wheel and tighten nuts to 140 Nm (103 ft. lbs.).
7. Remove stand(s) and lower vehicle.
8. Check and, if necessary, adjust wheel alignment. See «WHEEL ALIGNMENT PROCEDURES»(/land-rover/discovery/l318-2002-2004/remont/wheel-alignment/#wheel-alignment-specifications-procedures__wheel-alignment-procedures) .
9. After check/adjustment of wheel alignment, ensure track rod adjuster clamp bolts are tightened. Tighten M8 bolts to 22 Nm (16 ft. lbs.) and M10 bolts to 33 Nm (24 ft. lbs.).

1. Raise front of vehicle.
2. Right hand drive models: Remove left front road wheel.
3. Left hand drive models: Remove right front road wheel.
4. Remove nut securing drag link to steering knuckle. (Scheme 51)
5. Using LRT-57-036, break taper joint and release drag link.
6. Loosen adjuster clamp bolts and unscrew ball joint and adjuster. (Scheme 52)
7. Remove clamps from adjuster and drag link.

Scheme 51

Scheme 52

1. Clean adjuster, clamps and drag link.
2. Fit clamps to drag link and adjuster. Screw in adjuster and ball joint.
3. Clean ball joint taper and taper seat.
4. Adjust length of drag link so that ball joint taper is centralized in steering knuckle.
5. Fit drag link to steering knuckle and tighten nut to 80 Nm (59 ft. lbs.).
6. Tighten drag link adjuster clamp bolts. Tighten M8 bolts to 22 Nm (16 ft. lbs.) and M10 bolts to 33 Nm (24 ft. lbs.).
7. Check steering linkage is centralized. See «STEERING LINKAGE - CENTRALIZE»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system__steering-linkage-centralize) .
8. Fit road wheel and tighten nuts to 140 Nm (103 ft. lbs.).
9. Remove stand(s) and lower vehicle.

1. Raise front of vehicle.
2. Right hand drive vehicles: Remove the left front road wheel.
3. Left hand drive vehicles: Remove the right front road wheel.
4. Remove nut and bolt securing damper to drag link and release damper.
5. Remove 2 nuts securing drag link to drop arm and steering knuckle.
6. Using LRT-57-036 break taper joints and remove drag link.
7. Loosen adjuster clamp bolts and remove ball joint and adjuster.
8. Remove clamps from adjuster and drag link.

Scheme 53

Scheme 54

Scheme 55

1. Clean adjuster, clamps and ball joint.
2. Fit clamps to drag link and adjuster. Screw in adjuster and ball joint.
3. Clean ball joint tapers and taper seats.
4. Fit drag link to drop arm and tighten nut to 80 Nm (59 ft. lbs.).
5. Adjust length of drag link so that ball joint taper is centralized in steering knuckle.
6. Fit drag link to steering knuckle and tighten nut to 80 Nm (59 ft. lbs.).
7. Tighten drag link adjuster clamp bolts. Tighten M8 bolts to 22 Nm (16 ft. lbs.) and M10 bolts to 33 Nm (24 ft. lbs.)
8. Align damper to drag link, fit nut and bolt and tighten to 125 Nm (92 ft. lbs.).
9. Check steering linkage is centralized. See «STEERING LINKAGE - CENTRALIZE»(/land-rover/discovery/l318-2002-2004/remont/manual-power-steering/#steering-system__steering-linkage-centralize) .
10. Fit road wheel and tighten nuts to 140 Nm (103 ft. lbs.).
11. Remove stand(s) and lower vehicle.

1. Raise front of vehicle.
2. Remove 2 nuts and bolts securing steering damper to drag link and chassis. (Scheme 56)
3. Compress damper and remove from vehicle.

Scheme 56

1. Position damper to chassis and drag link. Fit nuts and bolts and tighten to 125 Nm (92 ft. lbs.).
2. Remove stand(s) and lower vehicle.

1. Remove driver-side air bag module: For 1999 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-98367-S07055353962001052200000). For 2000 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-97309-S10991298842001043000000). For 2001 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-150004-S28748992082002110400000). For 2002 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-150779-S36619872062002112100000). For 2003 models, see «DRIVER-SIDE AIR BAG MODULE»(/land-rover/discovery/l318-2002-2004/remont/airbag/#air-bag-restraint-systems). For 2004 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-170459-S26085835042005011000000).
2. Disconnect horn multiplug. (Scheme 57)
3. Centralize steering wheel with road wheels in straight ahead position.
4. Restrain steering wheel and loosen self locking nut securing steering wheel to column.
5. Release steering wheel from column.
6. Remove and discard self locking nut.
7. Remove steering wheel.
8. Attach tape across edge of rotary coupler to retain correct setting. (Scheme 58)
9. Release 2 clips securing each horn button to steering wheel. (Scheme 59)
10. Remove screw securing horn earth lead to steering wheel.
11. Disconnect radio and cruise control multiplugs.
12. Remove 2 screws securing radio switches to steering wheel.
13. Remove radio switches from steering wheel.
14. Remove 2 screws securing cruise control switches to steering wheel.
15. Remove cruise control switches from steering wheel.
16. Remove horns from steering wheel.

Scheme 57

Scheme 58

Scheme 59

1. Fit horn switches to steering wheel and secure with clips.
2. Fit and tighten screw securing horn earth lead to steering wheel.
3. Fit cruise control switches to steering wheel and secure with screws.
4. Fit radio switches to steering wheel and secure with screws.
5. Connect radio and cruise control multiplugs.
6. Remove tape from rotary coupler.
7. Ensure road wheels are in straight ahead position and indicator cancelling cam are aligned horizontally.
8. Fit steering wheel to column.
9. Connect horn multiplug.
10. Fit and tighten new self-locking nut securing steering wheel to column to 43 Nm (32 ft. lbs.).
11. Fit drivers airbag: For 1999 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-98367-S07055353962001052200000) . For 2000 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-97309-S10991298842001043000000) . For 2001 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-150004-S28748992082002110400000) . For 2002 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-150779-S36619872062002112100000) . For 2003 models, see «DRIVER-SIDE AIR BAG MODULE»(/land-rover/discovery/l318-2002-2004/remont/airbag/#air-bag-restraint-systems) . For 2004 models, see «DRIVER-SIDE AIR BAG MODULE»(ref-170459-S26085835042005011000000) .

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• CHECK/TOP-UP -- PAS/ACE RESERVOIRS
• SPECIFICATIONS & PROCEDURES
• ACCESSORY DRIVE BELT (DISCOVERY II)
• ROTARY COUPLER (CLOCKSPRING)
• WHEEL ALIGNMENT PROCEDURES
• HYDRAULIC SYSTEM - BLEED
• STEERING LINKAGE - CENTRALIZE
• SHAFT - INTERMEDIATE & UNIVERSAL JOINT - STEERING COLUMN