Land Rover Lesson 2 Auto Trans Coolingine Rover Manual

							EGR valve3
Hose, EGR4
Water outlet assembly5
EGR valve6
Hose, EGR inlet7
Fuel cooler8
Expansion tank9
Hose, fuel cooler10
Cooling fan11
Hose, radiator to expansion tank12
Shroud, lower13
Radiator14
Shroud, upper15
Hose and thermostat assembly16
Water pump17
Water inlet connector18
Heater hose, thermostat19
Engine CoolingLesson 2 – Powertrain
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							Cooling System Component Layout – Manual Gearbox, With FBH
Heater hose, in and out1
Connections for rear heater (optional)2
EGR valve3
Water outlet assembly4
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Lesson 2 – PowertrainEngine Cooling 
						

							Hose, EGR5
EGR valve6
Hose, EGR inlet7
FBH8
Fuel cooler9
Expansion tank10
Hose, fuel cooler11
Cooling fan12
Hose, radiator to expansion tank13
Shroud, lower14
Radiator15
Shroud, upper16
Hose and thermostat assembly17
Water pump18
Water inlet connector19
FBH hose, in and out20
Engine CoolingLesson 2 – Powertrain
129Technical Training (G421101) 
						

							Cooling System Component Layout – Automatic Gearbox Without FBH
Heater hose, in and out1
Connections for rear heater (optional)2
EGR valve3
Water outlet assembly4
(G421101) Technical Training130
Lesson 2 – PowertrainEngine Cooling 
						

							Hose, EGR5
EGR valve6
Hose, EGR inlet7
Fuel cooler8
Expansion tank9
Transmission oil cooler pipes10
Hose, fuel cooler11
Cooling fan12
Hose, radiator to expansion tank13
Shroud, lower14
Radiator15
Shroud, upper16
Hose and thermostat assembly17
Water pump18
Water inlet connector19
Heater hose, thermostat20
Engine CoolingLesson 2 – Powertrain
131Technical Training (G421101) 
						

							Cooling System Component Layout – Automatic Gearbox, With FBH
Heater hose, in and out1
Connections for rear heater (optional)2
EGR valve3
Water outlet assembly4
(G421101) Technical Training132
Lesson 2 – PowertrainEngine Cooling 
						

							Hose, EGR5
EGR valve6
FBH7
Fuel cooler8
Expansion tank9
Transmission oil cooler pipes10
Hose, fuel cooler11
Cooling fan12
Hose, radiator to expansion tank13
Shroud, lower14
Radiator15
Shroud, upper16
Hose and thermostat assembly17
Water pump18
Water inlet connector19
FBH hose, in and out20
GENERAL
The cooling system employed is of the pressure relief
by-pass type, which allows coolant to circulate around
the engine and the heater circuit while the thermostat
main valve is closed. The primary function of the
cooling system is to maintain the engine within an
optimum temperature range under changing ambient
and engine operating conditions. Secondary functions
are to provide heating for the passenger compartment
and cooling for the transmission fluid and engine oil.
The cooling system comprises:
•A radiator
•An intercooler
•A passenger compartment heater matrix
•Two fuel coolers
•Two Exhaust Gas Recirculation (EGR) coolers
•A Fuel Burning Heater (FBH) (Market dependant)
•A coolant pump
•A Pressure Relief Thermostat (PRT)
•An expansion tank
•An electro-viscous fan
•Connecting hoses and pipes.
ENGINE COOLING SYSTEM
The coolant is circulated by a centrifugal type pump
mounted on the front of the engine and driven by the
ancillary drive polyvee belt. The coolant pump
circulates coolant around the cylinder block and cylinder
heads via a chamber located in the vee of the engine.
Some of the coolant flow is diverted through the
integrated fuel and engine oil coolers. Having passed
through the engine and oil coolers, the coolant returns
to the thermostat housing via the by-pass pipe. Coolant
also circulates through the EGR coolers to the heater
matrix and returns to the engine side of the PRT.
On vehicles fitted with FBH, the coolant circulates
through the EGR coolers to the FBH unit (whether
active or not) and then on to the heater matrix. The
coolant then returns to the engine side of the PRT
The PRT housing contains a normal thermostat, which
is positioned such that the waxs temperature is
controlled by both the coolant from the radiator and the
bypass. This results in the thermostat being able to vary
its opening temperature dependant on ambient
conditions. The PRT also contains a sprung loaded
valve, which limits the amount flow using the bypass.
This means that the engine can run without coolant
flowing through the bypass temporarily, to improve
heater performance.
Engine CoolingLesson 2 – Powertrain
133Technical Training (G421101) 
						

							The radiator is a cross flow type with an aluminium
matrix and has a drain tap on the lower RH rear face.
The lower radiator mountings are located part way up
the end tanks. The mountings are fitted with rubber
bushes, which sit on the upper chassis rails. The radiator
upper is mounted by pins, which are pushed through
rubber bushes mounted in the Front End Carrier (FEC)
above the radiator.
The intercooler is attached to the bottom of the radiator
by two pins, which locate into fittings in the radiator
end tanks.
The radiator top hose is connected to the PRT by the
bypass hose and the bottom hose is directly connected
to the outlet side of the thermostat housing.
The expansion tank is fitted forward of the LH
suspension turret in the engine compartment. The
expansion tank allows for the expansion of the coolant
as the engine gets hot and also supplies the engine with
coolant as the coolant in the engine contracts. The tank
also allows any air trapped in the coolant to be removed.
The liquid cooled transmission fluid cooler (automatic
models only) is mounted in the cold side radiator end
tank. It is positioned in the middle of the LH end tank.
The 2nd fuel cooler is fed from the cold side end tank
of the radiator from a sub cooled section and returns
into the PRT housing on the radiator side.
On vehicles fitted with a FBH, the unit is located
forward of the LH suspension turret. Coolant flows
through the FBH whether it is active or not. The exhaust
from the burner is vented into the front LH wheel arch.
For additional airflow through the radiator matrix,
particularly when the vehicle is stationary, there is an
engine driven electro-viscous fan unit fitted to the rear
of the radiator. The fan is used for engine cooling and
for Air Conditioning (A/C) system cooling. This unit
functions as a normal viscous fan, but with electronic
control over the level engagement of the clutch. The
Engine Control Module (ECM), which determines the
required fan speed, controls the level of clutch
engagement. The ECM determines engagement based
on the coolant, charge air, ambient and transmission oil
temperatures and the A/C pressure. The fan is mounted
using a left hand thread.
The viscous fan unit is electronically controlled by the
ECM to optimise fan speed for all operating conditions.
NOTE: If the electrical connections to the viscous fan
are disconnected the fan will idle and overheating may
result. The ECM stores the appropriate fault codes in
this case.
(G421101) Technical Training134
Lesson 2 – PowertrainEngine Cooling 
						

							ENGINE COOLING SYSTEM OPERATION
Cooling System Coolant Flow – Manual Gearbox Without FBH
Engine CoolingLesson 2 – Powertrain
135Technical Training (G421101) 
						

							Cooling System Coolant Flow – Manual Gearbox With FBH
(G421101) Technical Training136
Lesson 2 – PowertrainEngine Cooling