The hoses should not sit short on the fittings.
Check the tightness of the clamps. If possible, use screw clamps.
Check the expansion tank cap gasket for damage.
Caution: Low coolant level may be due to improperly tightened cap.
Check the tightness of the radiator drain tank.
If the coolant level drops quickly and no leaks are found, check the cooling system with the engine warmed up. To do this, warm up the engine and let it idle until the fan turns on. Watch for coolant leaking out in the area of the water pump.
A noticeable drop in coolant level and/or oil in the coolant, as well as white smoke in the exhaust when the engine is hot, indicates a faulty cylinder head gasket.
Note: It is often quite difficult to locate the leak. Therefore, it is recommended to carry out a pressure test of the cooling system using a special device in a workshop. In this case, you can also check the safety valve in the expansion tank cap. Valve opening pressure: 1.2-1.4 bar.