Renault Megane II Coolant Replacement

General requirements for the cooling system

Important! When performing work requiring complete draining of the fluid from the cooling system, always rinse the system with clean water and blow it through with compressed air to remove water residues.

Fill with coolant, remove the air from the system and measure its actual frost resistance. The system must ensure frost resistance:

at a temperature down to –25 °C ± 2 for countries with a cold and temperate climate;
at a temperature down to –40 °C ± 2 for countries with a very cold climate.

Precautions: before starting the work, cover the electrical equipment devices with plastic bags.

Replacing the coolant

Replacement interval: as recommended by the manufacturer, the coolant should be replaced after 6 years of operation or 90 000 km of mileage, whichever comes first.

Necessary materials and tools

coolant — use GLACEOL RX (type D);
clean cloth;
container for draining the coolant with a volume of at least 10 litres;
pliers.

Important! The coolant must be replaced with the engine cold.

Procedure

We place the vehicle on a lift or over an inspection pit.

Vehicle on the lift — We place the vehicle on a lift or over an inspection pit

We open the expansion tank cap. We remove the engine undertray and the engine splash guard.

Removing the undertray and splash guard — We remove the engine undertray and the engine splash guard

Squeezing the clip ears of the expansion tank hose — We squeeze the clip ears of the expansion tank supply hose securing clip and slide the clip along the hose

We remove the hose from the radiator stub and drain the fluid into the container placed underneath. After the coolant has finished draining, we refit the hose onto the stub.

Pouring the coolant into the expansion tank — We pour the fluid into the expansion tank up to the «max» mark on the tank wall

Removing air locks

We start the engine and warm it up to operating temperature (until the fan switches on). After that we stop the engine and check the coolant level. If necessary, we top it up in the expansion tank to the «max» mark.

Temperature monitoring: while the engine is running, the coolant temperature must be monitored using the gauge.

If the gauge has reached the overheating zone but the radiator fan has not switched on:

switch on the heater and check what air passes through it;
if the heater supplies warmed air — the fan is most likely faulty;
if it supplies cold air — an air lock has formed in the engine cooling system.

To remove the air lock:

We switch off the engine and let it cool down.
We unscrew the filler neck cap.
We start the engine and let it run for 3–5 minutes.
We close the filler neck cap.

Tip: for better filling of the system without air locks, the radiator hoses should be periodically squeezed by hand.

After replacement: a few days after operating the vehicle following the coolant replacement, its level must be checked. If necessary, we top up the fluid.

Additional information: Method of replacing the coolant on a Renault Megane 2