Characteristic | Meaning |
| Maximum system pressure: |
|
| Models with petrol engine: |
|
| Engine 1.4 l | 1.2 bar |
| Diesel models | 1.2 bar |
Thermostat
Characteristic | Meaning |
| Operating temperature: |
|
| Starts to open when | 89°C |
| Valve lift height | 7.5 mm |
General description
Hermetically sealed cooling system (pressure above atmospheric), turns on the water pump (is driven on 1.4 and 1.6 petrol engines by a toothed belt, and on 2.0 l engines and diesel models by an auxiliary belt), aluminum cross flow radiator, electric fan, thermostat, heater core and associated hoses and switches.
The system works like this: Cold coolant from the base of the radiator passes through the lower hose to the water pump, which pumps it through the engine and engine oil cooler passages (where is available). After cooling the cylinders, combustion chambers and valve seats, the coolant enters the thermostat, which is initially closed. The coolant passes through the heater and returns through the cylinder block to the water pump.
While the engine is cold, the coolant circulates only through the cylinder block, its head and the heater. When the liquid heats up to a certain temperature, the thermostat opens and the liquid passes through the upper hose to the radiator. Passing through the radiator, the liquid is cooled by the air flow generated by the car's movement. When necessary, this flow is increased by the operation of the fan.
On diesel models, coolant flows through the engine oil cooler or intercooler and around the turbocharger (where is available). On models with automatic transmission, coolant is also passed through a transmission fluid cooler.
As the engine heats up, the coolant expands and some of it moves into the expansion tank. After the system cools down, the liquid returns from the tank to the radiator.
The electric fan, installed behind the radiator, is started by a thermal switch that is triggered at a certain coolant temperature.
Precautions
Do not remove the expansion tank filler cap or disconnect any parts of the cooling system until the engine has cooled down, as this will cause hot steam and liquid to escape. If for some reason the cap is removed, carefully relieve the pressure in the system. To do this, cover the cap with a thick cloth folded several times and slowly unscrew it until you hear a hissing sound. When the hissing stops (pressure released), slowly unscrew the lid and remove it; if the hissing noise continues, stop and wait until it subsides. Keep your face away from the filler neck and protect your hands with gloves.
If antifreeze comes into contact with your skin or the painted surfaces of your car, immediately wash away spilled drops with plenty of water. Never leave antifreeze in an open container or spilled on the garage floor - the deadly poisonous liquid can attract children and pets with a pleasant smell.
When working on models equipped with air conditioning, follow the Precautions given in Section Removal and installation of heater components (scenic models).
(Text of the original source on this website: www.RenaultBook.ru)