Attention! Replacement of air conditioning system hoses must be carried out at a service station that has equipment to depressurize the system.
High temperatures in the engine compartment cause rubber and plastic hoses to deteriorate. Periodic inspection should help identify cracks, loose fasteners, local hardening and leaks.
Pic. 2.11. Radiator Hose Damage: a - burnt areas; b - softened places; c - hardening; d - swollen or oiled areas of the hose
Check hoses for burnt areas that can lead to costly engine repairs (pic. 2.11).
«Softness» hose indicates internal wear that can contaminate the cooling system and clog the radiator.
A rigid hose can collapse at any time. Tightening the clamps that secure the rigid hose to the nozzle will not ensure the tightness of the connection and will not stop the leak.
A swollen hose or oil-soaked hose ends indicate a possible leak in the lubrication system.
Vacuum hoses
A leak in the vacuum hose means that air is being sucked into the hose (does not come out of the hose), and this makes the leak very difficult to detect.
The detection method is to use an old vacuum hose as a kind of stethoscope. Hold one end of the hose close to your ear (but not in the ear), and use the other end to inspect the area around the suspected leak. When the end of the hose is directly over the leak, a hissing sound will be clearly audible through the hose. Contact with hot and moving parts must be avoided, as the test must be carried out with the engine running.
Attention! When examining a vacuum hose with a stethoscope, be careful not to allow your body or hoses to come into contact with moving engine parts such as drive belts, fan, etc.
Fuel hoses
The fuel supply system is under pressure, therefore, before disconnecting the pipelines, it is necessary to reduce the pressure in the system.
Warning! Gasoline is extremely flammable, therefore, when working with elements of the fuel supply system, it is prohibited to use fire, sparking devices, open flammable light devices, and smoking. Avoid sparking when working with wires and electrical devices.
Warning! Since gasoline is a carcinogen, it must be prevented from getting on the body and the paintwork of the car. Otherwise, immediately wash the area with soap and water.
Check all rubber fuel hoses for wear and tear. Especially carefully check the kinks in the hoses in front of the clamps in the places where the hoses are attached to the fuel pump, fuel filter and carburetor.
For replacement, it is necessary to use high quality fuel lines, which are identified by the inscription «Ruroelastomer» on the hose. Under no circumstances should a vacuum hose, a cleaned plastic tube or a water hose be used to replace a fuel line.
Typically, spring clips are used to fasten fuel lines to nozzles, which lose their elasticity over time, and can also «spring back» when they are removed. Therefore, every time a hose is replaced, it is recommended to replace all spring clips with screw clips.
Metal pipelines
Pieces of metal tubing are often used as a fuel line between the fuel pump and the carburetor. Make sure the tubing is not bent or corrugated and that there are no splits in the kinks.
To replace a piece of metal fuel line, only a seamless steel tube should be used, as copper and aluminum tubes cannot withstand vibration during engine operation.
Check the metal pipes of the brake system at their connections to the brake master cylinder and pressure regulator (if it is used) for cracks in the pipes or loose connections. Any evidence of brake fluid leakage means that the brake system needs to be inspected immediately and completely.