When checking the oil and electrolyte levels, also inspect the cooling system hoses. Check the clamps for tightness every three months or after long, fast driving. If the clamps cut too deeply into the hoses, slide the clamp along the hose or replace the hose. If the hose becomes stiff or cracks begin to develop, replace it immediately.
If a hose ruptures, stop the engine as quickly as possible. Carefully open the hood (there may be a stream of hot coolant under the hood). As soon as possible, place a piece of thick fabric over the tear. Place another piece of cloth over the radiator cap and twist it to relieve pressure. The stream will subside, and it will be possible to determine the fault more accurately. If the problem is with one of the smaller hoses, it may be possible to short-circuit the break. If one of the larger hoses ruptures, surgical tape or duct tape can be used as a temporary measure. A more radical temporary measure would be to cut the hose at the break and insert a piece of metal tubing, securing the hose with two clamps. This device will hold the fluid well until you can install a new hose.
Never pour cold water into a hot engine if it is not running, this is the surest way to cause cracks in the cylinder head.
Finally, if a hose bursts, you need to find out the cause before taking any action. The rupture may be caused by aging of the hose or careless handling. In this case, nothing more is required than replacing the hose. However, if it was a new hose, the cause should be determined immediately.
How to identify low-quality hoses
Both upper and lower radiator hoses do hard work in adverse conditions. They are subjected to pressures of up to 1.1 bar and temperatures in excess of 100°C and must flow approximately 30,000 litres of coolant per hour. Therefore, it is necessary to monitor their condition.
Swollen hose
A good test for a hose is to feel it for softness and porosity. Often these defects appear as swollen areas on the hose. The most likely cause is exposure to oil. The hose can burst at any time when it is hot and under pressure.
Cracked hose
Cracked hoses occur because people usually just look at the hoses but don't feel them to see if they are firm. Wear of the hose end (due to weak clamping).
Loose clamps are a common cause of damage to coolant hoses. The tube-hose connection wears out and fluid leaks out when the engine is hot.
Dirt in the cooling system
Dirt, rust and scale in the cooling system will cause wear on the inside of the hose. This can be felt externally as a soft or refined place.