Cooling system — leak test (Renault Scenic 1)

9. Check the cooling system hoses for porosity by squeezing and bending them. Replace hardened or swollen hoses with new ones. The hoses should not sit too shallowly on the connecting fittings.

10. Check the strength of the hose clamps. If necessary, replace the old clamps with clamps with screw clamps.

11. Check the condition of the expansion tank cap gasket (see arrow in illustration).

Caution! Low coolant level may be caused by incorrect tightening of the expansion tank cap.

If the fluid level drops frequently and you cannot find the leak, check the cooling system with the engine warm. To do this, warm up the engine and let it idle until the fan turns on. Check if fluid is leaking around the water pump.

Significant losses of coolant and (or) the presence of oil in it, as well as white clouds of exhaust gases with a warm engine indicate a defect in the cylinder head gasket.

Warning! It can sometimes be difficult to locate a leak. In this case, it is recommended to perform a pressure test of the cooling system by contacting a workshop, as this requires a special device. In this case, you can also check the pressure relief valve on the expansion tank cap.