Cooling System
| Capacity (engine only) | 4.8 litres (8.5 Imp pints) |
| Capacity (complete system) | 7.1 litres (12.5 Imp pints) |
| Maximum system pressure | 1 bar |
| Water pump rotation speed | Engine rpm x 1.05 |
Thermostat
| Travel (minimum) | 7.5 mm |
| Opening temperature: | |
| Starts to open | 79ºC (174ºF) |
| Fully open | 82ºC (180º F) |
Cooling fan
| Cut-in temperature: | |
| 1st speed | 86º to 90ºC (186º to 194ºF) |
| 2nd speed | 90º to 94ºC (194º to 201°F) |
Coolant temperature switch
| Operational temperatures | 105 to 112ºC (221 to 233ºF) |
| Radiator Cap pressure | 1 bar |
Torque wrench settings (Nm…..lbf ft)
| Coolant pump upper stud | 16…..12 |
| Coolant pump lower bolt | 8…..6 |
| Housing inlet elbow | 8…..6 |
| Housing to block | |
| 8 mm bolts | 31…..22 |
| 10 mm bolts | 51…..37 |
General information
The cooling system is of the pump-assisted thermal syphon type and is pressurised
by means of a pressure valve filler cap.
The main components of the system are the radiator, the coolant pump, the thermostat, the cooling fan, the heater and the connecting hoses.
Cold coolant from the bottom of the radiator is pumped into the passages of the cylinder block and head. Heat from the combustion chambers and moving parts of the engine is absorbed by the coolant which is then directed to the upper section of the radiator.
The passage of air through the radiator cools the coolant as it passes down through the matrix and the cycle is then repeated.
To accelerate the warming-up process when starting the engine, and thereafter to maintain the correct operating temperature, a thermostat is fitted in the coolant outlet from the engine to the radiator top hose.
When the coolant is cold the thermostat is closed and circulation is limited to the engine coolant passages by means of a bypass route.
As coolant temperature rises, the thermostat opens to allow coolant to flow through the radiator.
The system is pressurised to raise the boiling point of the coolant. This allows the engine to achieve its most efficient operating temperature as well as reducing the amount of coolant needed.
Hot coolant is tapped from the system to supply the vehicle heater matrix and also to supply heat to the throttle body to improve fuel vaporisation.
The cooling fan is driven by an electric motor and this only cuts in above a certain temperature when activated by a coolant temperature sensor switch.
The coolant pump is located in the front of the cylinder block at the timing case end and is driven by the timing belt.
The heater is located centrally under the facia and supplies warm air for interior heating or windscreen demisting. Hot coolant is piped from the engine through a heater matrix and back to the engine when a manually operated valve is opened.
Fresh air inlets are located at the ends of the facia and any stale air from the car interior is exhausted through slots in the tailgate closure recess.
Air conditioning is available as an optional extra on some models. To allow for fitting of the system, the engine crankcase is modified to suit.
