Home/Land Rover/Discovery/Land Rover Discovery L318 (2002-2004)/Repair manual/Accessory Drive Belts/Drive Belt Routing, Cooling System Draining & Refilling, & …
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Drive Belt Routing, Cooling System Draining & Refilling, & Specifications Land Rover Discovery L318

Accessory Drive Belts 6 illustrations ~686 words

ENGINE IDENTIFICATION

ApplicationEngine
Discovery II
2001-024.0L
2003-044.6L
Range Rover
2001-024.6L

ENGINE IDENTIFICATION

COMPONENT LOCATIONS

For component locations and cooling system flow (Scheme 1)or (Scheme 2).

Scheme 1

Scheme 1: COMPONENT LOCATIONS

Scheme 2

Scheme 2

DRAINING & REFILLING COOLING SYSTEM

WARNINGDO NOT remove expansion tank pressure cap when engine is hot. Serious injury such as scalding can be caused by escaping steam or hot coolant.
  1. Visually check engine and cooling system for signs of coolant leaks. Examine hoses for signs of cracking, distortion and security of connections. Position drain tray to collect coolant. Remove expansion tank filler cap.
  2. Remove drain plugs from left and right sides of engine block and allow cooling system to drain. (Scheme 3) Disconnect bottom hose from radiator and allow cooling system to drain. (Scheme 4)
  3. Disconnect top hose from thermostat and position open end of hose below level of coolant pump inlet, to allow coolant to drain from the system.

Scheme 3

Scheme 3

Scheme 4

Scheme 4

Scheme 5

Scheme 5
  1. Flush system with water under low pressure. Apply Loctite 577 to engine block drain plugs. Install drain plugs to side of engine block. Tighten to specification. See «TORQUE SPECIFICATIONS»(/land-rover/discovery/l318-2002-2004/remont/accessory-drive-belts/#drive-belt-routing-cooling-system-draining-refilling-specifications__torque-specifications).
  2. Connect bottom hose to radiator and top hose to thermostat housing. Secure with hose clips. Prepare coolant to required concentration. Release top hose from retaining lugs on fan cowl, leaving hose to rest on lugs. Remove bleed screw from top hose. (Scheme 5)
  3. Unclip bleed hose from battery box. Remove expansion tank from its mounting bracket. Slowly fill expansion tank with approximately 7 pints (4 liters) of coolant. Raise expansion tank approximately 8" (20 cm) vertically to allow coolant to drain into system.
  4. Refill coolant expansion tank until a steady flow of coolant is emitted from bleed hole. Install bleed screw. With expansion tank still raised, continue filling system until coolant level reaches base of expansion tank filler neck. Install expansion tank filler cap, expansion tank to its mountings and clip bleed hose to battery box.
  5. Install top hose into its lugs on fan cowl. Start and run engine until normal operating temperature is reached. Check for leaks. Switch off engine and allow to cool. Check for leaks and top-up coolant to cold level mark on expansion tank
  1. Raise and support vehicle. Remove expansion tank filler cap to assist draining. Position a container under radiator. Remove drain plug from base of radiator. Allow coolant to drain. If system is only being partially drained, go to «Refill»(/land-rover/discovery/l318-2002-2004/remont/accessory-drive-belts/#drive-belt-routing-cooling-system-draining-refilling-specifications) .
  2. Reposition container. Remove left cylinder block drain plug and allow coolant to drain. DO NOT remove right cylinder block drain plug. Clean drain plug threads. Apply a coating of Loctite 577 and install plug to block. Tighten securely.
  1. Ensure sufficient coolant solution is available. Inspect radiator drain plug "O" ring, replace as required. Install drain plug to radiator. Tighten to specification. See «TORQUE SPECIFICATIONS»(/land-rover/discovery/l318-2002-2004/remont/accessory-drive-belts/#drive-belt-routing-cooling-system-draining-refilling-specifications__torque-specifications) . Remove safety stands and lower vehicle.
  2. Disconnect radiator bleed hose at the radiator. Blow through hose to clear any residual coolant and reconnect hose. Fill expansion tank until coolant is level with base of neck.
  3. Start engine, continue filling at expansion tank until coolant level stabilizes at the COLD LEVEL marking. Operate engine until thermostat opens and top hose becomes warm to touch. Stop engine, allow to cool. Check coolant level, top-up as necessary. Install expansion tank filler cap.

TROUBLE SHOOTING

Note. Critical warning messages relating to the complete cooling system are displayed on the message center in the lower section of the instrument panel, should a fault occur in any of the separate systems.

COOLING SYSTEM FAULTS

This section covers mechanical faults that could occur in the complete cooling system

  1. Engine (coolant) cooling. See «ENGINE (COOLANT) COOLING SYSTEM»(/land-rover/discovery/l318-2002-2004/remont/accessory-drive-belts/#drive-belt-routing-cooling-system-draining-refilling-specifications) .
  2. Engine oil cooling. See «ENGINE OIL COOLING SYSTEM»(/land-rover/discovery/l318-2002-2004/remont/accessory-drive-belts/#drive-belt-routing-cooling-system-draining-refilling-specifications__engine-oil-cooling-system) .
  3. Transmission oil cooling. See «TRANSMISSION OIL COOLING SYSTEM»(/land-rover/discovery/l318-2002-2004/remont/accessory-drive-belts/#drive-belt-routing-cooling-system-draining-refilling-specifications__transmission-oil-cooling-system) .

Symptom - Engine Overheating

Possible CauseRemedy
Engine Coolant LowAllow engine to cool. Top up expansion tank to correct level, with engine running at idle. Check cooling system for leaks & repair, if necessary.
Loose Drive BeltCheck or repair drive belt tensioner or repair drive belt, if necessary.
Coolant In Radiator FrozenSlowly thaw & drain cooling system.
Air Flow Through Radiator Restricted Or BlockedApply air pressure to engine side of radiator to clear obstruction. If mud or dirt is evident, carefully clean using a hose.
External Leaks From Water Pump, Engine Gaskets, Thermostat Housing Or Pipe/HosesPerform visual inspection & repair as necessary.
Viscous Fan Not Operating Correctly Or InoperativeReplace viscous fan unit.
Thermostat Seized In Closed PositionCheck radiator bottom hose for coolant flow through radiator. If cold, a faulty thermostat is confirmed. Replace thermostat.
Air In Cooling SystemCheck coolant level. Run engine at fast idle (approximately 2,000 RPM) with expansion tank cap off. Top up coolant level with engine at idle & refit expansion tank cap.
Air Conditioning Condenser Fans Not Operating Correctly Or InoperativeCheck air conditioning operation.
Temperature Gauge Or Sender Unit Giving Inaccurate ReadingsSubstitute parts & compare new readings.
Coolant Leakage Across Cylinder Head GasketCarry out cylinder pressure test to determine if pressure is leaking into cooling system, causing over pressurizing & loss of coolant. Replace cylinder head gasket.
Engine Oil Contamination Of Cooling System Due To LeakingReplace cylinder head gasket.
Coolant Contamination Of Lubrication SystemReplace intake manifold or front cover gaskets as necessary.

SYMPTOM - ENGINE OVERHEATING

Symptom - Engine Runs Cold

Possible CauseRemedy
Thermostat Seized In Open Or Partially Open PositionRemove thermostat housing & check operation of thermostat. Replace thermostat as necessary.
Temperature Gauge Or Sender Unit Giving Inaccurate ReadingsSubstitute parts & compare new readings.
Viscous Fan Not Operating CorrectlyReplace viscous fan unit.
Air Conditioning Condenser Fans Operating ContinuouslyRefer to TestBook/T4 scan tool.

SYMPTOM - ENGINE RUNS COLD

ENGINE OIL COOLING SYSTEM

Possible CauseRemedy
Air Flow Through Oil Cooler Matrix Restricted Or BlockedApply air pressure to engine side of radiator to clear obstruction. If mud or dirt is evident, carefully clean using a hose.
Blocked Or Damaged Oil Cooler Or Pipe/Hoses Restricting Engine Oil FlowPerform visual inspection for damage & repair damaged components where necessary.
Oil Cooler Relief Valve Seized In Closed PositionRemove & check relief valve. Replace, if necessary.

SYMPTOM - ENGINE OIL OVERHEATING

TRANSMISSION OIL COOLING SYSTEM

Possible CauseRemedy
Air Flow Through Oil Cooler Matrix Restricted Or BlockedApply air pressure to engine side of radiator to clear obstruction. If mud or dirt is evident, carefully clean using a hose.
Damaged Oil Cooler Or Pipe/Hoses Restricting Gearbox Oil FlowPerform visual inspection for damage & repair damaged components where necessary.
Vehicle Being Driven In Wrong GearAdvise owner/driver accordingly.

SYMPTOM - GEARBOX OIL OVERHEATING

BELT ADJUSTMENT

Note. If reinstalling original belt, mark direction of rotation on belt for installation reference before removing.

ApplicationSpecification
All Models(1)
(1) No adjustment is necessary, drive belt tension is maintained by automatic belt tensioner.
(1)No adjustment is necessary, drive belt tension is maintained by automatic belt tensioner.

BELT ADJUSTMENT

Scheme 6

Scheme 6: Routing Illustrations

COOLING SYSTEM SPECIFICATIONS

ApplicationSpecification
Discovery II
Coolant Replacement Interval(1)
Coolant Capacity - Refill12.1 Qts. (11.5 L)
Coolant Capacity - Fill From Dry13.1 Qts. (12.4 L)
Expansion Tank Cap Pressure20 psi (1.4 bar)
Serpentine Belt Replacement Interval75,000 Miles (5 Years)
Thermostat Initial Opening179°F (82°C)
Thermostat Fully Open204°F (96°C)
Range Rover
Coolant Replacement Interval(1)
Coolant Capacity - Refill11.9 Qts. (11.3 L)
Expansion Tank Cap Pressure15 psi (1.0 bar)
Serpentine Belt Replacement Interval60,000 Miles Or 48 Months
Thermostat Initial Opening176-194°F (80-90°C)
(1) Inspect coolant level every week and replace every 30,000 miles or 24 months. Use an ethylene glycol based anti-freeze (containing no methanol) with non-phosphate corrosion inhibitors suitable for use in aluminum engines. Use a 50 percent mixture. DO NOT allow mixture to exceed 60 percent or fall below 25 percent.
(1)Inspect coolant level every week and replace every 30,000 miles or 24 months. Use an ethylene glycol based anti-freeze (containing no methanol) with non-phosphate corrosion inhibitors suitable for use in aluminum engines. Use a 50 percent mixture. DO NOT allow mixture to exceed 60 percent or fall below 25 percent.

COOLING SYSTEM SPECIFICATIONS

TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
Cylinder Block Drain Plugs (Discovery II) (1)22 (30)
Viscous Fan Assembly-To-Water Pump41 (56)
Viscous Fan-To-Coupling Bolts18 (24)
Water Pump Pulley Bolts16 (22)
Water Pump-To-Engine Bolts16 (22)
INCH Lbs. (N.m)
Radiator Drain Plug (Range Rover)53 (6)
(1) Apply Loctite 577 to cylinder block drain plugs.
(1)Apply Loctite 577 to cylinder block drain plugs.

TORQUE SPECIFICATIONS