The mark on the expansion tank of the cooling system shows the maximum liquid level in the system at a temperature of 20°C.
Draining the coolant must be carried out in the following order. Prepare a container for draining the coolant and a clean rag. Unscrew the cover (30, see fig. 3.17) on the expansion tank of the cooling system.
1 - radiator; 2 - temperature sensor; 3, 17, 20, 22 - hose; 5 - bolt (М6х25); 6 - thermostat in the housing; 7 - gasket; 3 - block head; 9, 13 - ring (20x3); 10 - heating hose; 11 - nut (M6); 12, 15, 16 - bolt; 14 - pipeline; 18 - heating pump; 19 - holder; 21 - air removal screw; 23 - timing cover; 24 - ring (68x5); 25 - engine pump; 26 - pulley; 27 - bolt (M6x16); 28 - nut (MB); 29 - expansion tank; 30 - tank cap
Loosen the screw (21, see fig. 3.17) to bleed air from the expansion tank of the radiator (only for vehicles equipped with manual transmission) or hose (22). Remove stiffening plate. Remove bolts (see fig. 3.56) and remove the engine accessory protection panel.
Remove the drain plug at the bottom of the radiator (pic. 1.137) cooling systems...
...and cork (arrow, fig. 3.138) drain hole on the cylinder block on the right side.
Drain the coolant and send it for recycling. Replace seal gasket (M14x1.5) cylinder block and tighten it to 25 Nm (2.5 kgf·m).
Refueling of the coolant must be carried out through the neck of the expansion tank in the following order. Replace the drain seal at the bottom of the radiator and tighten its plug to 2.5 Nm (0.25 kgf·m).
Turn on the ignition. Set heater control to maximum temperature. Set the fan to the lowest speed. At the same time, the valves of the heater unit open, and its additional pump starts to work (18, see fig. 3.17).
Remove the screw (21) to remove air from the engine cooling system. Line the filler neck with a clean rag. Slowly fill the coolant through the neck of the expansion tank of the radiator to the maximum mark (2, fig. 3.139).
Wait until through the radiator vent (or 21 screw holes) coolant will not come out without air bubbles. Close the cap on the expansion tank and tighten the screw on the pipe (22) torque 8.0 Nm (0.8 kgf·m). Remove the rag and send it for recycling.
Bleed the engine cooling system and check for leaks. Start the engine, warm it up to operating temperature until the thermostat opens. Check the tightness of the cooling system and the liquid level in the expansion tank of the cooling system.