1999 LAND ROVER DEFENDER radiator cap

LUBRICANTS, FLUIDS AND CAPACITIES
3
INFORMATION CAPACITIES
The following capacity figures are approximate and are provided as a guide only.
Capacities (approx.)* Litres Pints
Engine sump oil - Td5 7.20...................................................... 12.67
Extra when refilling after fitting new filter 1.00.......................... 1.76
Manual gearbox 2.38............................................................... 4.19
Transfer gearbox oil 2.30......................................................... 4.00
Front differential 1.70............................................................... 3.00
Rear differential
90 Models 1.70............................................................... 3.00
110 Models 2.26............................................................. 4.00
Power steering box and reservoir LHD 2.90............................ 5.00
Power steering box and reservoir RHD 3.40............................ 6.00
Swivel pin housing oil/grease (each) 0.35................................ 0.60
Fuel tank usable fuel
90 Models 60.00............................................................... 13.20 gall
110 & 130 Models 75.00................................................... 16.50 gall
Cooling system - Td5 13.00....................................................... 22.88
Washer bottle 3,0................................................................... 5.28
NOTE: * All levels must be checked by dipstick or level plugs as applicable.
ANTI-FREEZE
PERCENTAGE CONCENTRATION - 50%
PROTECTION - LOWER TEMPERATURE LIMIT
Complete protection
Vehicle may be driven away immediately from cold,
-33°C (-36°F).
Safe limit protection
Coolant in semi-frozen state. Engine may be started
and driven away after warm-up period, -41°C (-42°
F).
Lower protection
Prevents frost damage to cylinder head, block and
radiator. Thaw out before starting engine, -47°C (-53°
F).
CAUTION: Anti-freeze content must never
be allowed to fall below 50% otherwise
damage to the engine is liable to occur.
Also, anti-freeze content should not exceed 60%
as this will greatly reduce the cooling effect of the
coolant.RECOMMENDED FUEL
Diesel fuel oil, distillate, diesel fuel, automotive gas or
Derv to British standard 2869, Class A1 or A2
Using diesel fuel with a class rating lower than stated
above could seriously impair vehicle performance.
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MAINTENANCE
9
MAINTENANCE INTERCOOLER / COOLING SYSTEM
1.Visually check for any obstructions in the
radiator and intercooler matrix and remove
debris as necessary.
2.Visually check fan blades for damage.
3.Check cooling, intercooler and heating systems
for leaks, hoses and oil pipes for security and
condition.
4.Check accessible hose clips for tightness.
5.Check coolant level, top-up if necessary
Cooling System Top-Up
1.With engine cold, remove expansion tank filler
cap.
2.Top-up with recommended mixture of coolant
until level reaches mark on expansion tank.
3.Fit expansion tank filler cap.
Intercooler Flush
1.Remove intercooler.See FUEL SYSTEM,
Repair.
2.Flush intercooler element using Unicorn
Chemicals’C’Solve following the manufaturers
instructions.
3.Thoroughly dry intercooler ensuring that no trace
of solvent remains in the element.
4.Refit intercooler.See FUEL SYSTEM, Repair.AMBIENT AIR PRESSURE (AAP) SENSOR - Td5
1.Check ambient air pressure sensor for damage.
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COOLING SYSTEM
3
DESCRIPTION AND OPERATION
NOTE: Inset A shows differences for Pre
EU3 models
1.Pressure cap
2.Overflow pipe
3.Heater return hose
4.Heater matrix
5.Heater inlet hose
6.Oil cooler return pipe - EU3 models
7.Connecting hose
8.Oil cooler housing assembly
9.Heater inlet pipe
10.Connecting hose
11.Outlet housing
12.Engine Coolant Temperature (ECT) sensor
13.Bleed screw
14.Radiator top hose
15.Radiator - upper
16.Intercooler
17.Gearbox oil cooler
18.Radiator - lower
19.Viscous fan
20.Drain plug
21.Connecting hose
22.Fuel cooler feed hose
23.Radiator bottom hose
24.Thermostat housing
25.Connecting hose
26.Coolant pump feed pipe
27.Coolant by-pass pipe
28.Radiator bleed pipe
29.Connecting hose
30.Coolant pump
31.Fuel cooler
32.Heater/expansion tank return hose
33.Expansion tank
34.EGR Cooler - EU3 models
35.Connecting hose - EU3 models
36.Connecting hose - EU3 models
37.Hose - EGR Cooler to oil cooler return pipe -
EU3 models
38.Radiator lower feed hose - Pre EU3 models
39.Oil cooler return pipe - Pre EU3 models
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26COOLING SYSTEM
6
DESCRIPTION AND OPERATION 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 below 1500 rev/min, 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 warm coolant through the
heater matrix to improve passenger comfort in cold conditions.
When the engine speed increases above 1500 rev/min 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
engines cooling needs at higher engine rev/min.
Outlet Housing
A cast aluminium outlet housing is attached to the cylinder head with three bolts and sealed with a gasket. Coolant
leaves the engine through the outlet housing and is directed through a hose to the heater matrix, the radiator or
the by-pass circuit.
An Engine Coolant Temperature (ECT) sensor is installed in a threaded port on the side of the outlet housing. The
sensor monitors coolant temperature emerging from the engine and sends signals to the Engine Control Module
(ECM) for engine management and temperature gauge operation.
Expansion Tank
The expansion tank is located in the engine compartment. The tank is made from moulded plastic and attached to
brackets on the right hand inner wing. A maximum coolant when cold level is moulded onto the tank.
Excess coolant created by heat expansion is returned to the expansion tank from the radiator bleed pipe at the top
of the radiator. An outlet pipe is connected into the coolant pump feed hose and replaces the coolant displaced by
heat expansion into the system when the engine is cool.
The expansion tank is fitted with a sealed pressure cap. The cap contains a pressure relief valve which opens to
allow excessive pressure and coolant to vent through the overflow pipe. The relief valve is open at a pressure of
1.4 bar (20 lbf.in) and above.
Heater Matrix
The heater matrix is fitted in the heater assembly inside the passenger compartment. Two pipes pass through the
bulkhead into the engine compartment and provide coolant flow to and from the matrix. The pipes from the
bulkhead are connected to the matrix, sealed with’O’rings and clamped with circular rings.
The matrix is constructed from aluminium with two end tanks interconnected with tubes. Aluminium fins are
located between the tubes and conduct heat from the hot coolant flowing through the tubes. Air from the heater
assembly is warmed as it passes through the matrix fins. The warm air is then distributed in to the passenger
compartment as required.
When the engine is running, coolant from the engine is constantly circulated through the heater matrix.
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COOLING SYSTEM
13
DESCRIPTION AND OPERATION When the coolant temperature is low, the heat emitted from the radiator does not affect the bi-metallic coil. The
valve remains closed, preventing fluid escaping from the reservoir into the fluid chamber. In this condition the fan
will’freewheel’at a slow speed.
As the coolant temperature increases, the heat emitted from the radiator causes the bi-metallic coil to tighten. This
movement of the coil moves the valve to which it is attached. The rotation of the valve exposes ports in the valve
plate which allow the silicone fluid to spill into the fluid chamber. As the fluid flows into the clearance between the
annular grooves in the drive plate and body, drag is created between the two components. The drag is due to the
viscosity and shear qualities of the silicone fluid and causes the drive plate to rotate the body and fan blades.
As the coolant temperature decreases, the bi-metallic coil expands, rotating the valve and closing off the ports in
the valve plate. When the valve is closed, centrifugal force pushes the silicone fluid through the return port,
emptying the fluid chamber. As the fluid chamber empties, the drag between the drive plate and the body is
reduced and the body slips on the drive plate, slowing the rotational speed of the fan.
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COOLING SYSTEM
1
ADJUSTMENT DRAIN AND REFILL
Service repair no - 26.10.01
WARNING: Hot coolant
Drain
1.Remove engine acoustic cover.
2.Visually check engine and cooling system for
signs of coolant leaks.
3.Examine hoses for signs of cracking, distortion
and security of connections.
4.Position drain tray to collect coolant.
5.Remove expansion tank filler cap.
6.Loosen clip screws securing air inlet hose to
intercooler and inlet manifold, release and
remove hose.
7.Release clip and disconnect bottom hose from
radiator.
8.Allow cooling system to drain.
9.Disconnect bottom hose from radiator.Refill
1.Flush system with water under low pressure.
2.Do not use water under high pressure as it could
damage the radiator.
3.Connect bottom hose to radiator and secure
hose with clip.
4.Prepare coolant to required concentration.
5.Position heater temperature control to maximum
hot position.
6.Remove bleed screw from top hose.
7.Fill system slowly through coolant expansion
tank until a steady flow of coolant is emitted from
the bleed hole in top hose.
8.Fit bleed screw to top hose.
9.Continue filling system until coolant level
reaches’MAX’mark on expansion tank.
10.Fit expansion tank filler cap.
11.Position air intake hose and tighten clip screws.
12.Start and run engine until normal running
temperature is reached.
13.If fitted, DO NOT operate air conditioning.
14.Switch off engine and allow to cool.
15.Check for leaks and top-up coolant to’MAX’
mark on expansion tank.
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82AIR CONDITIONING
2
REPAIR MOTOR - CONDENSER FAN
Service repair no - 82.15.01
Remove
1.Remove 6 screws and remove radiator grille.
2.Disconnect fan multiplug and release multiplug
holder from retaining clip.
3.With assistance remove 4 nuts and bolts
securing motor to condenser.
4.Remove motor.
Refit
5.Position motor to condenser and with assistance
tighten nuts and bolts to8 Nm (6 lbf.ft).
6.Connect motor multiplug.
7.Position radiator grille and secure with screws.RECEIVER DRIER
Service repair no - 82.17.03
Remove
1.Recover refrigerant from A/C system.See
Adjustment.
2.Remove 2 bolts securing pipe unions to receiver
drier.
3.Release pipes and discard’O’rings.
CAUTION: Immediately cap all air
conditioning pipes to prevent ingress of
dirt and moisture into the system.
4.Remove 2 bolts securing receiver drier mounting
bracket to chassis.
5.Remove receiver drier, slacken clamp bolt and
remove bracket.
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