belt LAND ROVER DISCOVERY 1999 Owner's Guide
[x] Cancel search | Manufacturer: LAND ROVER, Model Year: 1999, Model line: DISCOVERY, Model: LAND ROVER DISCOVERY 1999Pages: 1529, PDF Size: 34.8 MB
Page 421 of 1529
COOLING SYSTEM - V8
26-2-6 DESCRIPTION AND OPERATION
Description
General
The cooling system used on the V8 engine is a pressure relief by-pass type system which allows coolant to circulate
around the cylinder block and the heater circuit when the thermostat is closed. With coolant not passing through the
radiator, this promotes faster heater warm-up which in turn improves passenger comfort.
A coolant pump is located in a housing at the front of the engine and is driven by a drive belt. The pump is connected
into the coolant passages cast in the cylinder block and pumps coolant from the radiator through the cylinder block.
A viscous fan is attached by means of a nut to the coolant pump pulley drive spindle. The fan draws air through the
radiator to assist in cooling when the vehicle is stationary. The fan rotational speed is controlled relative to the running
temperature of the engine by a thermostatic valve regulated by a bi-metallic coil.
The cooling system uses a 50/50 mix of anti-freeze and water.
Thermostat housing
A plastic thermostat housing is located behind the radiator. The housing has three connections which locate the
radiator bottom hose, top hose and coolant pump feed hose. The housing contains a wax element and a spring loaded
by-pass flow valve.
Thermostat - Main valve
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid engine
warm-up. The thermostat is closed at temperatures below approximately 82°C (179°F). When the coolant
temperature reaches approximately 82°C the thermostat starts to open and is fully open at approximately 96°C
(204°F). In this condition the full flow of coolant is directed through the radiator.
The thermostat is exposed to 90% hot coolant from the engine on one side and 10% cold coolant returning from the
radiator bottom hose on the other side.
Hot coolant from the engine passes from the by-pass pipe through four sensing holes in the flow valve into a tube
surrounding 90% of the thermostat sensitive area. Cold coolant returning from the engine, cooled by the radiator,
conducts through 10% of the sensitive area.
In cold ambient temperatures, the engine temperature is raised by approximately 10°C (50°F) to compensate for the
heat loss of 10% exposure to the cold coolant returning from the bottom hose.
By-pass flow valve
The by-pass flow valve is held closed by a light spring. It operates to further aid heater warm-up. When the main valve
is closed and the engine speed is at idle, the coolant pump does not produce sufficient flow and pressure to open the
valve. In this condition the valve prevents coolant circulating through the by-pass circuit and forces the coolant through
the heater matrix only. This provides a higher flow of coolant through the heater matrix to improve passenger comfort
in cold conditions.
When the engine speed increases above idle the coolant pump produces a greater flow and pressure than the heater
circuit can take. The pressure acts on the flow valve and overcomes the valve spring pressure, opening the valve and
limiting the pressure in the heater circuit. The valve modulates to provide maximum coolant flow through the heater
matrix and yet allowing excess coolant to flow into the by-pass circuit to provide the engine's cooling needs at higher
engine rev/min.
Page 423 of 1529
COOLING SYSTEM - V8
26-2-8 DESCRIPTION AND OPERATION
Coolant pump
1Pulley flange
2Body
3Impeller4Gallery
5Inlet connection
The coolant pump is attached to the front of the cylinder block with nine bolts and sealed between the pump housing
and the cylinder block with a gasket. The pump comprises a shaft which passes through an alloy housing. The outer
end of the shaft has a flange which allows for the attachment of the pump drive pulley which is secured with three
bolts. The drive pulley is driven by the grooved auxiliary drive belt and rotates at the same speed as the crankshaft.
The inner end of the shaft is fitted with an impeller which draws coolant from the thermostat housing and circulates it
through the galleries in the cylinder block and through the heater matrix.
The shaft is supported on bearings in the housing which are packed with grease and sealed for life. A seal is
positioned in the housing to further protect the bearings from the ingress of coolant. The seal is manufactured from a
synthetic material which will allow for expansion of the casing when hot coolant is present.
The cast alloy housing has a hose connection which provides the attachment for the coolant pump feed hose. The
cast housing connects with galleries in the cylinder block and distributes coolant from the pump impeller into the
galleries and water jackets.
Page 434 of 1529
COOLING SYSTEM - V8
REPAIRS 26-2-19
Gasket - coolant pump
$% 26.50.02
Remove
1.Remove auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
2.Drain cooling system.
+ COOLING SYSTEM - V8,
ADJUSTMENTS, Drain and refill.
3.Remove 3 bolts securing pulley to coolant
pump and remove pulley.
4.Release clip and disconnect feed hose from
coolant pump. 5.Remove 9 bolts securing coolant pump,
remove pump and discard gasket.
Refit
1.Clean coolant pump and mating face.
2.Fit new gasket and coolant pump to cylinder
block. Fit bolts and tighten to 24 Nm (18 lbf.ft).
3.Connect feed hose to coolant pump and secure
with clip.
4.Ensure mating faces of coolant pump pulley
and flange are clean. Fit pulley and tighten
bolts to 22 Nm (16 lbf.ft).
5.Fit auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
6.Refill cooling system.
+ COOLING SYSTEM - V8,
ADJUSTMENTS, Drain and refill.
Page 445 of 1529
MANIFOLDS AND EXHAUST SYSTEMS - V8
30-2-10 REPAIRS
Heat shield - brake servo - With
Secondary Air Injection
$% 30.10.48
Remove
1.Release fixings and remove battery cover.
2.Disconnect battery earth lead.
3.Remove nut securing heat shield bracket to
valance.
4.Remove 2 bolts securing heat shield and
remove heat shield.
Refit
1.Fit heat shield, tightening bolts to 25 Nm (18
lbf.ft) and nut to 10 Nm (7 lbf.ft).
2.Connect battery earth lead.
3.Fit battery cover and secure with fixings.
Gasket - inlet manifold - lower
$% 30.15.08
Remove
1.Remove both rocker covers.
l
+ ENGINE - V8, REPAIRS, Gasket
- rocker cover - LH.
l
+ ENGINE - V8, REPAIRS, Gasket
- rocker cover - RH.
2.Release and disconnect LH injector harness
and multiplugs.
3.Release 3 clips securing top hose and remove
top hose.
4.Remove auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
Page 448 of 1529
MANIFOLDS AND EXHAUST SYSTEMS - V8
REPAIRS 30-2-13
20.Remove inlet manifold gasket.
21.Remove gasket seals.
Refit
1.Clean all traces of sealant from cylinder head
and cylinder block notches.
2.Clean mating faces of cylinder block, cylinder
head and inlet manifold.
3.Apply sealant, Part No. STC 50550 to cylinder
head and cylinder block notches.
4.Fit new gasket seals, ensuring ends engage
correctly in notches.
5.Fit new inlet manifold gasket.
6.Position gasket clamps and fit bolts, but do not
tighten at this stage.
7.Position inlet manifold to engine. Fit manifold
bolts and, working in the sequence shown,
tighten bolts initially to 10 Nm (7 lbf.ft) then to
51 Nm (38 lbf.ft).
8.Tighten gasket clamp bolts to 18 Nm (13 lbf.ft).
9.Connect fuel pipe.
10.Clean top hose outlet pipe mating faces.
11.Fit new 'O' ring to outlet pipe.
12.Position outlet pipe, fit bolts and tighten to 22
Nm (16 lbf.ft).
13.Position alternator, fit bolts and tighten to 45
Nm (33 lbf.ft).
14.Position PAS pump to auxiliary housing and
locate housing on engine. Fit bolts and tighten
to 40 Nm (30 lbf.ft).15.Fit and tighten auxiliary housing nut to 10 Nm (7
lbf.ft).
16.Fit bolts securing PAS pump and tighten to 22
Nm (16 lbf.ft).
17.Position oil cooling pipe bracket fit bolt and
tighten to 22 Nm (16 lbf.ft).
18.Fit and tighten PAS pump high pressure pipe.
19.Position jockey pulley and tighten bolt to 50 Nm
(37 lbf.ft).
20.Clean PAS pump pulley mating faces.
21.Position PAS pump pulley, fit bolts and tighten
to 22 Nm (16 lbf.ft).
22.Clean ACE pump dowels and dowel holes.
23.Position ACE pump, fit bolts and tighten to 22
Nm (16 lbf.ft).
24.Fit auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
25.Secure injector harness and connect injector
multiplugs.
26.Position top hose and secure clips.
27.Fit rocker covers.
l
+ ENGINE - V8, REPAIRS, Gasket
- rocker cover - LH.
l
+ ENGINE - V8, REPAIRS, Gasket
- rocker cover - RH.
28.Check and top up PAS fluid
Page 705 of 1529
STEERING
57-12 DESCRIPTION AND OPERATION
PAS pump - V8
1Bolt 2 off
2Nut
3Stud
4Auxiliary housing
5PAS pump6Outlet
7Inlet
8Bolt 3 off
9Drive pulley
The PAS pump is located on the auxiliary housing and is attached by two bolts, the bolts go through flanged bushes
in the auxiliary housing. 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.
Page 707 of 1529
STEERING
57-14 DESCRIPTION AND OPERATION
PAS pump - diesel
1Drive pulley
2Mounting bracket
3Bolt 2 off
4Bolt
5PAS pump
6Coupling7Auxiliary housing
8Outlet
9Inlet adaptor pipe and seal
10Bolt 2 off
11Bolt 2 off
12Bolt 3 off
The PAS pump is located on the auxiliary housing, two bolts go through the PAS pump, mounting bracket and into
the auxiliary housing. One bolt also attaches the mounting bracket to the PAS pump, two bolts secure the mounting
bracket to the auxiliary housing. An inlet adaptor pipe with a seal is secured to the bottom of the pump with two bolts.
A drive pulley is attached to the pump drive shaft with three bolts, and is belt driven at a ratio of 1.35 crankshaft
revolutions to 1 of the drive pulley. A coupling on the rear of the PAS pump rotates the water pump impeller located
in the auxiliary housing. Fluid is supplied to 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.
Page 732 of 1529
STEERING
REPAIRS 57-39
Refit
1.Clean seal recess, output shaft, end cover and
mating face.
2.Lubricate new end cover 'O' ring with clean
PAS fluid. Fit 'O' ring to end cover.
3.Position output shaft, fit bolts and tighten to 88
Nm (65 lbf.ft).
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 lbf.ft).
10.Secure lock washer to drop arm nut.
11.Fit steering box.
lFor V8 models:
+ STEERING, REPAIRS, Power
steering box - V8.
lFor LHD diesel models:
+ STEERING, REPAIRS, Power
steering box - LHD - diesel.
lFor RHD diesel models:
+ STEERING, REPAIRS, Steering
box - RHD - diesel.
Pump - power steering - V8
$% 57.20.14
Remove
1.Remove auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
2.Remove cable tie securing harness to air intake
hose.
3.Loosen 3 clips securing air intake hose, release
and remove hose.
Note: Pre 03 MY air intake hose illustrated.
4. Models with ACE: Remove 3 bolts securing
ACE pump, release pump and position aside.
Page 734 of 1529
STEERING
REPAIRS 57-41
Refit
1.Position PAS pump to auxiliary housing and
locate housing to engine. Fit and tighten
auxiliary housing bolts to 40 Nm (30 lbf.ft).
2.Tighten auxiliary housing nut to 10 Nm (7 lbf.ft).
3.Fit bolts securing PAS pump and tighten to 22
Nm (16 lbf.ft).
4.Position PAS pump pipe bracket, fit and tighten
bolt to 22 Nm (16 lbf.ft).
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 lbf.ft).
8.Clean PAS pump pulley mating faces.
9.Position PAS pump pulley, fit bolts and tighten
to 22 Nm (16 lbf.ft).
10. Models with ACE: Clean ACE pump dowels
and dowel holes. Position ACE pump, fit bolts
and tighten to 25 Nm (18 lbf.ft).
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
lbf.ft).
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.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive..
15.Bleed PAS system.
+ STEERING, ADJUSTMENTS,
Hydraulic system - bleed.
Page 735 of 1529
STEERING
57-42 REPAIRS
Pump - power steering - diesel
$% 57.20.14
Remove
1.Remove auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
2.Remove 3 bolts securing PAS pump pulley and
remove pulley.
3.Position tray to catch spillage, release PAS
pump pressure pipe.
4.Remove clip and release PAS pump inlet hose.
CAUTION: Always fit plugs to open
connections to prevent contamination.
5.Remove 4 bolts and remove PAS pump.
6.Remove bolt, and remove mounting bracket
from PAS pump.
7.Remove 2 bolts, remove low pressure adaptor
pipe and discard 'O' ring. Refit
1.Clean PAS pump and adaptor pipe.
2.Fit new 'O' ring to adaptor pipe, fit pipe and
tighten bolts to 10 Nm (7 lbf.ft).
3.Position mounting bracket to PAS pump, fit but
do not tighten bolt.
4.Position PAS pump and align pump drive to
coolant pump. Fit and tighten bolts to 25 Nm
(18 lbf.ft).
5.Tighten mounting plate bolt to 25 Nm (18 lbf.ft).
6.Clean PAS pump and pipe union.
7.Fit and tighten PAS pump pressure pipe to 20
Nm (15 lbf.ft).
8.Fit PAS pump inlet hose and secure with clip.
9.Clean PAS pump and pulley mating faces.
10.Position PAS pump pulley, fit and tighten bolts
to 10 Nm (7 lbf.ft).
11.Fit auxiliary drive belt.
+ CHARGING AND STARTING,
REPAIRS, Belt - auxiliary drive.
12.Bleed power steering system.
+ STEERING, ADJUSTMENTS,
Hydraulic system - bleed.