3.9. Check of a state and replacement of the hoses located in a motive compartment
Performance of replacement of hoses of the K/V refrigerator lines should be charged to the experts of a workshop of car service having the necessary equipment and having due qualification, allowing to make a safe discharge of system. Do not disconnect refrigerator lines at all until the system is not completely discharged!
Under the influence of the high temperatures taking place in a motive compartment of the car, material of the rubber and plastic hoses laid in it begins to collapse eventually. It is regularly necessary to examine all hoses located under a cowl on existence of cracks, traces of leaks, signs of hardening of material and weakening of nipple connections.
Detailed information on check of a condition of hoses of cooling systems of the engine and heating of salon is stated in the Section Check of a Condition of Components.
For fastening on the unions of some, but not everything, hoses collars are used. Check reliability of tightening of hose collars, - weakening of their fastening leads to development of leaks. If the hose is put on the union without collar, make sure that its end remains rather elastic for a dense staving of a surface of the union.
Usually all vacuum hoses which are especially used in systems of decrease in toxicity of the fulfilled gases are marked with a color code, or in their walls of a vplavlena color strips. In various systems various requirements can be imposed to thickness of walls of the vacuum hoses used in them. Hoses have to provide various resistance to a collapse, temperature influences and other factors. You watch that replaceable hoses answered in the parameters removed from the car.
Usually rather authentically it is possible to estimate a condition of a vacuum hose only having removed it from the car. If it is necessary to remove more than one hose, previously take care of their accurate marking for the purpose of respect for correctness of connection at assembly.
During check of a vacuum hose, do not forget to estimate also a condition of its plastic nipple connections - examine the union on existence of cracks and make sure of density of landing of a hose on it. At a tension on the union the hose should not be deformed unevenly, causing depression losses.
The short piece of a vacuum hose with an internal diameter about 7 mm represents a fine stethoscope by means of which sources of losses of depression rather easily come to light. One end of a hose nestles on the checked surface, the second - on an ear. Depression losses are always followed by hissing.
When listening components try not to touch such moving components in a motive compartment as driving belts, blades of a krylchatka of the fan, etc.!
Metal lines (each 15 000 km of a run)
Sections of metal tubes are often used as fuel lines. Attentively check all rigid fuel lines for existence of dents, excesses and other deformations. Make sure of lack of cracks and signs of the beginning of their education.
If any of sections of the metal line is subject to replacement, use as replaceable only a seamless steel tube. Copper and aluminum tubes do not suit for use as replacement as do not provide due resistance to impact of the vibrations arising in system during the operation of the engine.
Attentively examine metal brake tubes in places of connection them to GTTs and the valve limiter (if that is provided). Pay attention to such defects as cracks, try to reveal signs of weakening of fastenings. In case of identification of traces of leaks it is necessary to check immediately a condition of all brake system in general.
Fuel hoses (each 30 000 km of a run)
At service of components of a power supply system it is worth to remember that gasoline is easily flammable liquid in the highest measure. Do not smoke near the venue of works, do not approach it with naked flame! Immediately collect all traces of the spilled fuel, put the rags impregnated with fuel and lubricants to such place where the probability of its casual ignition is absolutely excluded! Always hold near at hand the class B fire extinguisher! Try not to allow hits of gasoline on open sites of skin - the long contact such is capable to lead to development of cancer diseases. Remember that the path of system of injection of fuel constantly is under the excessive internal pressure which has to be without fail dumped prior to work (see the Head of the Power supply system, release and decrease in toxicity of the fulfilled gases).
Check all rubber fuel hoses for existence of signs of aging of material and other defects. Pay special attention to the condition of sites of an excess and areas located just before the ends which are put on unions.
As replaceable lines only high-quality fuel hoses have to be used. It is not necessary to install to the highway power supply systems not strengthened vacuum hoses, transparent plastic tubes or garden hoses at all. Usually for fixing of fuel hoses on unions collars of spring type are used. Such collars lose durability of the landing over time, besides, often unexpectedly come off at the time of a hose detachment. It will be reasonable to replace such collars more reliable and safe worm or screw.