Checking the condition of the hoses in the engine compartment and replacing them
Warning. It makes sense to have the replacement of the air conditioner refrigerant pipes entrusted to a specialist from a dealership auto service center who has the equipment to safely remove the refrigerant from the system. Do not replace tubes when the system is filled.
General information
1. High temperatures in the engine compartment will greatly contribute to the deterioration of rubber and plastic hoses/tubes used in the engine, accessories and emission control system. Periodic inspections should identify cracks, loose clamps, damage to hose materials and leaks.
2. Information regarding cooling system hoses can be found in paragraph 11.
3. Some hoses are secured in the connections with clamps. When inspecting such hoses, check the tightness of the clamps to avoid leaks. If clamps are not used in the connection, then during inspection, make sure that the hoses at the connection points have not expanded and/or hardened, which can also cause a leak.
Vacuum hoses
4. Typically, vacuum hoses, especially those in the emission control system, have corresponding colors or colored stripes. Depending on the purpose, they vary in wall thickness, tensile strength and temperature resistance. When replacing hoses, make sure that the new hoses are the same type as those being replaced.
5. In some cases, to fully check the condition of the hose, it is necessary to disconnect it. If you have disconnected several hoses, it is a good idea to label the removed hoses and their corresponding fittings to avoid any potential errors during subsequent installation.
6. When checking the vacuum hoses, don't forget to check the plastic connecting tees for cracks, and also make sure the hoses are seated correctly on the fittings without any distortions, which will help prevent leaks.
7. To detect damage to vacuum hoses, you can use a small piece of vacuum hose with a diameter of 8-10 mm as a stethoscope. Place one end of the stethoscope to your ear and slowly move the other end along the hoses and tees: a characteristic hissing-whistle sound will indicate the presence of a microcrack.
Caution! When working with the vacuum stethoscope, be careful not to touch rotating engine parts such as drive belts, cooling fans, etc.
Fuel lines
Caution! Diesel fuel is not as volatile as gasoline, but it is still flammable, so take special precautions when working on any part of the fuel system. Do not smoke or use open flames or portable electric lighting devices that are not equipped with protective screens. Do not work in a garage that uses gas-powered equipment, such as a water heater or clothes dryer. Avoid contact with diesel fuel - wear protective clothing, goggles (mask) and gloves. When performing any work on the fuel system, keep a fire extinguisher handy. Work only in a well-ventilated area.
8. Check all rubber fuel hoses for internal damage (soft to the touch outer surface) and abrasions. Also check for cracks where the hoses bend and where the hoses connect to the pipes, such as where the hose is connected to the fuel filter pipe.
9. When replacing, purchase only high-quality hoses specifically designed for use in fuel injection systems.
Caution! When replacing, use only hoses of the same type as those being replaced.
10. Spring type clamps are commonly used in the fuel system. Such clamps may become loose after some time, and when removed, they may "shoot" and fly off in an unknown direction. When replacing hoses, it is recommended to simultaneously replace all factory spring clamps with more reliable worm-type clamps.
Metal pipelines
11. Metal pipes are often installed in the section between the fuel pump and the fuel injection unit. When checking, make sure there are no bends, wrinkles or incipient cracks on the surface of the pipeline.
12. If any section of a metal pipeline is to be replaced, then only the new section made of seamless steel tubing should be used for this purpose. Copper or aluminum sections should not be installed as they are not strong enough to withstand engine vibration.
13. Inspect the metal brake system lines leading to the master cylinder and pressure regulator valve (if it is used), and make sure there are no cracks on the surface of the pipeline and loose connections. Any signs of brake fluid leakage should be a signal for an immediate inspection of the brake system.
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