Note. The M4R engine has a dual circuit cooling system with two thermostats, one on the water pump and the other in the water box.
Removing the thermostat from the water pump
Place the car on a lift. Remove the engine undertray.
Drain the liquid from the engine cooling system.
Open the clamp (1) on the coolant inlet pipe using pliers with remote grip for elastic clamps (Mot. 1448). Disconnect the hose (2) from the inlet pipe.
Remove:
- bolts (3) fixing the inlet pipe;
- inlet pipe (4);
- thermostat.
Setting the thermostat on the water pump
Install:
- thermostat to the water pump in the direction shown in the figure;
- inlet pipe;
- inlet pipe bolts.
Torque tighten the coolant inlet pipe mounting bolts 17 Nm. Connect the coolant inlet pipe.
Install the water pump inlet hose clamp.
Pour fluid into the engine cooling system.
Install the engine undertray.
Removing the thermostat housing at the outlet of the cylinder head
Remove:
- engine crankcase mounting bolts;
- protective screen.
Drain the liquid from the engine cooling system.
Remove the coolant temperature sensor.
Remove the bolt (1) attaching the foot of the transmission breather tube. Move the bracket aside (2) transmission breather tubes.
Remove clamps (3) fixing the cooling system hoses on the thermostat housing.
Disconnect and move aside the cooling system hoses from the thermostat housing.
Disconnect the ball head of the multifunction switch cable (10) on the gearbox with a clamp.
Unlock the multi-function switch cable sheath stopper (11) on the gearbox.
Move the gear selector cable aside.
Remove:
- fastening bolts (12) thermostat housing;
- thermostat housing;
- thermostat housing gasket.
When installing, tighten the bolts securing the thermostat housing to 25 Nm to the required torque.
Removing the thermostat from the housing
Remove the thermostat (5).
Install all parts in reverse order.