1999 LAND ROVER DISCOVERY engine

STEERING
DESCRIPTION AND OPERATION 57-15
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
pressurised. 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 pressurisation/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.
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.

STEERING
57-18 ADJUSTMENTS
Hydraulic system - bleed
$% 57.15.02
Bleed
1.Clean 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.

+ CAPACITIES, FLUIDS,
LUBRICANTS AND SEALANTS, Fluids.
CAUTION: Ensure no dirt is allowed to enter
the steering reservoir when the cap is
removed.
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.
CAUTION: Do not hold steering at full lock
for longer than 10 seconds.
6.Stop engine.
7.Clean spilled PAS fluid from steering box and
surrounding area.
CAUTION: Power steering fluid will damage
paint finished surfaces. If spilled,
immediately remove fluid and clean area
with water.
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.
Steering linkage - centralise
$% 57.35.05
The following procedure assumes that the front
wheel alignment is correctly adjusted.
Adjust
1.Raise front of vehicle, and position the road
wheels at straight ahead.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Remove nut securing drag link to drop arm.
Using tool LRT-57-036 break taper joint and
release drag link from drop arm.
3.Fit centralising bolt to steering box and ensure
that front road wheels are in the straight ahead
position.
4.Loosen clamp bolts on drag link.

STEERING
57-20 ADJUSTMENTS
Power steering pressure check - diesel
models
$% 57.90.10.01
Check
1.Fit gauge and hose LRT- 57-005 to valve
assembly LRT- 57-001 and tighten union.
2.Fit 2 hoses LRT-57-002 to valve assembly
LRT- 57-001 and tighten unions
3.Fit adaptor and hose set LRT-57-041 to LRT-
57-002.
4.Disconnect battery earth lead.
5.Remove engine acoustic cover.
6. LHD only: Remove underbelly panel.

+ EXTERIOR FITTINGS, REPAIRS,
Panel - underbelly.7. LHD only: Disconnect MAF sensor multiplug,
release clips from air cleaner and move intake
hose aside. Discard seal.
8.Position container to collect PAS fluid spillage,
and syphon fluid from PAS reservoir.
9. LHD only: Release PAS reservoir from
mounting move aside, for access to
turbocharger intercooler pipe.
10.Remove vacuum hose from turbocharger
intercooler pipe.
11. LHD only: Release clips and disconnect
turbocharger intercooler pipe from
turbocharger and intercooler.
12.Clean steering box pipe housing.
M57 0902
M57 0903
M57 0904

STEERING
ADJUSTMENTS 57-21
13.Remove bolt from steering box pipe retaining
clip. Leaving the PAS reservoir oil pipe in place,
release pipe retaining clip and PAS cooler pipe
from steering box, discard the seal.
14.Fit tool LRT-57-041 to steering box housing.
15.Fit seal to PAS oil cooler pipe.
16.Fit PAS cooler pipe to LRT-57-041 align the
retaining clip to pipes and tighten bolt to 24 Nm
(18 lbf.ft).
17.Connect test hoses LRT-57-002 to LRT-57-
041 and tighten unions. Ensure all pipes and
fittings are clear of engine rotating parts.18.Hang pressure gauge in a safe position under
bonnet.
19. LHD only: Fit turbocharger intercooler feed
pipe and vacuum connection and fit PAS
reservoir to mounting bracket. Fit air intake
hose to turbocharger and air cleaner and
connect multiplug to MAF sensor. The above
parts must be refitted in order to run the
engine.
20.Fill PAS reservoir, connect battery earth lead.
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 is free from leaks and
maintain maximum fluid level during test.
22.Open the test valve on LRT-57-001 and start
the engine.
23.With the engine at idle and normal running
temperature, slowly turn the steering wheel and
hold on lock.
24.Note reading on pressure gauge.
25.Repeat pressure check on opposite lock, again
noting the reading on the pressure gauge.
26.The test pressure should be between 21 and 62
bar, (300 to 900 lbf/in
2. Pressure will rise to 62
bar (900 lbf/in2) when held on full lock.
27.With the engine at idle, centralise the steering
wheel. Pressure should read 7 bar (100 lbf/in
2)
or below.
28.Pressure outside the above tolerance indicates
a fault.
29.To determine if fault is in steering pump or
steering rack, close the valve on LRT-57-001
for a maximum of five seconds. Pump damage
may occur if test valve is closed for longer
periods.
30.If the gauge does not register between 75 and
103 bar, (1500 lbf/in
2) (maximum pump
pressure), the pump is faulty.
31.If maximum pump pressure is obtained,
suspect the steering box.
32.On completion, stop engine, disconnect battery
earth lead and syphon fluid from PAS reservoir.
33. LHD only: Disconnect multiplug from MAF
sensor, remove air intake hose clips and move
hose aside.
34. LHD only: Release PAS reservoir from
mounting, for access to turbocharger
intercooler pipe.Remove vacuum hose from
turbocharger intercooler pipe.Release clips and
disconnect intercooler pipe from turbocharger.
35.Remove test equipment from tool LRT-57-041.
36.Remove bolt and clip from steering box.
37.Release PAS cooler pipe from tool LRT-57-041
and discard seal. leaving PAS reservoir oil pipe
in place, release tool LRT-57-041 from
steering box and discard seal.

STEERING
ADJUSTMENTS 57-23
9.Release clips and remove air intake hose from
air cleaner housing.
Note: Pre 03 MY air intake hose illustrated.
10.Discard intake 'O' ring and move intake aside
for access.
11.Loosen union securing high pressure pipe to
PAS pump and release pipe.12.Fit adaptor LRT-57-034A to high pressure port
of PAS pump.
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. Dependant on road
surface.
28.With the engine at idle, centralise 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.

STEERING
57-24 ADJUSTMENTS
33.On completion stop engine, disconnect battery
earth lead and syphon 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
lbf.ft).
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.
Power steering pressure check - V8 RHD
models
$% 57.90.10.01
Check
1.Fit gauge and hose LRT-57-005 to valve
assembly LRT-57-001, tighten union.
2.Fit 2 hoses LRT-57-002 to valve assembly
LRT-57-001 and tighten unions.
3.Fit adaptor hoses LRT-57-041 to LRT-57-002
and tighten unions.
4.Disconnect battery earth lead.
5.Remove 5 screws securing front splash shield
to chassis. Remove shield.
6.Clean PAS fluid reservoir around filler cap and
fluid level indicators.

STEERING
ADJUSTMENTS 57-25
7.Syphon PAS fluid from reservoir.
8.Position container to collect PAS fluid spillage.
9.Clean steering box pipe pipe housing.
10.Remove bolt securing pipe clip to steering box.
Leaving the feed pipe from PAS reservoir in
place, release clip and PAS cooler pipe from
steering box. Discard lower 'O' ring.
11.Fit LRT-57-041 adaptor to steering box.
12.Fit PAS cooler pipe to LRT-57-041, align
retaining clip and tighten Allen bolt to 25 Nm (18
lbf.ft).
13.Hang pressure gauge in a safe position under
bonnet.
14.Remove PAS reservoir filler cap, fill to level
indicator and refit cap.
15.Connect battery earth lead.
16.Start engine and allow air to bleed from PAS
system by turning steering from lock to lock.
Stop engine and check PAS fluid level.
17.Ensure steering system and test equipment are
free from leaks.
18.Open test valve on LRT-57-001 and start
engine.
19.With the engine at idle, slowly turn the steering
wheel and hold on full lock.
20.Note the pressure reading on LRT-57-005.21.Repeat the pressure check for the opposite full
lock.
22.Test pressure should be between 21 and 62
bar, (300 to 900) psi. Dependant on road
surface.
23.With the engine at idle, centralise the steering
wheel. Pressure should read 7 bar (100 psi) or
below.
24.Pressure outside the above tolerance indicates
a fault.
25.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.
26.If gauge does not register between 75 and 103
bar, (1500 psi), (maximum pump pressure), the
pump is faulty.
27.If maximum pump pressure is correct suspect
the steering box.
28.On completion stop engine, disconnect battery
earth lead and syphon fluid from PAS reservoir.
29.Remove test equipment from LRT-57-002.
30.Remove bolt and clip from steering box.
31.Release PAS cooler pipe from LRT-57-041 and
discard 'O' ring. Leaving PAS reservoir oil feed
pipe in place, release LRT-57-041 from
steering box and discard 'O' ring.
32.Fit new 'O' rings to PAS cooler pipe.
33.Fit PAS cooler pipe to steering box, align
retaining clip, fit bolt and tighten to 25 Nm (18
lbf.ft).
34.Remove PAS reservoir filler cap, fill to level
indicator and refit cap.
35.Clean chassis member.
36.Fit splash shield and secure with screws.
37.Connect battery earth lead.
38.Start engine.
39.Start engine and allow air to bleed from PAS
system, by turning steering from lock to lock.
40.Visually check PAS system for leaks.
41.Check power steering fluid, if aerated, wait until
fluid is free from bubbles then top-up reservoir
to 'UPPER' level mark.
42.Visually check PAS system for leaks.
43.Dismantle test equipment.

STEERING
REPAIRS 57-29
12. RH drive models with ACE: Position ACE
control arms to access steering box bolts.
13.With assistance remove 4 securing bolts and
remove steering box.
14.Remove centralising bolt from steering box. Refit
1.Fit centralising bolt to steering box.
2. With assistance, position steering box, fit bolts
and tighten to 90 Nm (66 lbf.ft).
3. RH drive models with 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 lbf.ft).
4.Position drag link, fit nut and tighten to 80 Nm
(59 lbf.ft).
5.Position Panhard rod, fit bolt and nut and
tighten to 230 Nm (170 lbf.ft).
6.Clean 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 lbf.ft).
9. RHD models: Fit oil filter and housing:
lClean oil filter housing and engine mating
faces.
lLubricate new 'O' ring with clean engine oil
and fit to housing.
lPosition oil filter housing and tighten bolts to
9 Nm (7 lbf.ft).
10.Ensure steering wheel is centralised. Fit
universal joint between steering box and
intermediate shaft and tighten bolts to 25 Nm
(18 lbf.ft).
11.Remove centralising bolt from steering box.
12.Fit road wheel(s) and tighten nuts to 140 Nm
(103 lbf.ft)..
13.Remove stand(s) and lower vehicle.
14.Check and top up engine oil.
15.Bleed PAS system.

+ STEERING, ADJUSTMENTS,
Hydraulic system - bleed.
16.Centralise steering linkage

+ STEERING, ADJUSTMENTS,
Steering linkage - centralise.