Recommended periodicity: each 12 000 km of run or 6 months.
Replacement of hoses on central air of air make at the service station having the equipment for check and filling of system.
High temperature serves in a motor compartment as the reason of deterioration of properties of rubber and plastic hoses. Periodic survey should help to reveal the cracks, the weakened fastenings, local hardenings and leaks.
If there were signs of leakage of any liquid, but you cannot define its type or an exact place of leak, it is necessary to enclose at storage of the car under it a big piece of paper or a fabric. It will help to find a place of leak and to identify following liquid on color. But keep in mind that some leaks can appear only at the working engine.
At violation of tightness of a vacuum hose air is sucked in in a hose (instead of leaves a hose) that complicates leak detection. For definition of leak it is possible to use an old vacuum hose as a stethoscope. Put one end of a hose to an ear (do not insert into an ear), another — to a place of prospective leak. In a leak place through a hose the hissing sound will be clearly audible. As check is carried out at operation of the engine, avoid contact to hot and moving details.
Precisely to define a place of leakage of fuel happens difficult until leak will not increase and becomes appreciable. Fuel starts to evaporate quickly as soon as it contacts with air, especially in a hot motor compartment. Small drops can disappear before you define a leak place. If there is a suspicion that the place of leakage of fuel is in area of a motor compartment, let's cool down to the engine and get it at an open cowl. As metal details decrease in the sizes in a cold condition, and rubber hoses are weakened at this time, any leaks become more appreciable at this time.
Leaks in system of cooling are usually found on a raid of white color or color of a rust in the field of leak.
Carefully check a radiator and hoses of cooling liquid on all length. Replace hoses with cracks, gaps and aging signs. Cracks are easier for finding if to press a hose. Pay special attention to collars of fastening of hoses to elements of system of cooling. Strongly tightened collars can become the reason of a gap or a hose puncture that will lead to leaks in cooling system. Examine all hoses and places of their connection. If leaks are found, replace them or the corresponding laying.
On cars with an automatic transmission check a condition of hoses of the heat exchanger of transmission oil.