Warning: Replacement of air conditioning hoses should be left to a dealer or a professional with the proper equipment to depressurize the system. Never remove air conditioning components or system hoses until the system has been depressurized.
Vacuum hoses
1. High temperatures under the hood can cause damage to rubber and plastic hoses used for the engine, auxiliary components and in the emission system.
2. Hoses should be periodically inspected for cracks, loose clamps, hardening and leaks.
3. Some vacuum hoses are attached to the fittings with clamps, the reliability of which must also be checked periodically to avoid leaks. Where clamps are not used, ensure that the end of the hose has not become stretched and/or stiffened, which can also cause leaks.
4. Typically, vacuum hoses, especially those in the emission system, are color-coded or marked with colored stripes molded into the hose. Different systems use hoses with different wall thicknesses, strengths and heat resistance. When replacing hoses, use only adequate replacements.
5. Often, in order to effectively check a hose, it must be removed from the vehicle. If more than one hose needs to be removed, make sure the hoses and their connections are labeled to avoid confusion when reinstalling them.
6. When checking the vacuum hoses, also inspect all plastic T-joints. Check them for cracks. Inspect the ends of the hoses for tightness at the joints; stretched ends can lead to leaks.
7. To detect vacuum leaks, you can use a small piece of vacuum hose (inner diameter 6 mm). Place one end of the hose to your ear and place the other end near the vacuum hose connections and joints. A hissing sound will indicate the presence of a vacuum leak.
Warning: When checking vacuum hoses for leaks, be careful not to touch rotating engine components such as drive belts, cooling fans, etc. with your body or the test hose.
Fuel hoses
8. Warning: There are a number of precautions that must be taken when inspecting or servicing fuel system components. Work in a well-ventilated area and keep open flames away from the work area (cigarettes, matches, etc.) or light bulbs (they may burst, causing the vapors to ignite). Wipe up any spilled fuel immediately and do not store fuel-soaked rags in areas where they may catch fire.
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9. Fuel lines are usually under slight pressure, so if it is necessary to disconnect fuel lines, be prepared for fuel to come out of the ends.
10. Check all rubber fuel lines for damage and abrasions. Pay particular attention to the bends of the hoses and the places where they attach to the fuel pump, fuel filter and carburetor.
11. High quality hoses, usually marked with the word Fluroelastomer, should be used to replace fuel line components. Never use unsecured vacuum hoses, plastic tubing or water hoses for this purpose.
12. Spring clamps are commonly used on fuel lines. These clamps weaken over time. Therefore, when removing the hose, it is recommended to replace these clamps with clamps with a screw.
Metal tubes
13. Metal tubes are often used between the fuel pump and the carburetor. Inspect the line carefully to ensure that the tubes are not bent or cracked at the bends.
14. When replacing a metal fuel line, use only seamless steel tube, as copper and aluminum tubes are not rigid enough to withstand engine vibration during operation.
15. Check the metal brake pipes where they connect to the master cylinder and brakes for cracks and for the strength of the connections. If you notice even the slightest sign of brake fluid leakage, immediately inspect the entire brake system.