4.5. Repair and replacement of fuel lines and connectors

Fuel is extremely flammable therefore during the work with any part of fuel system take additional precautionary measures. You do not smoke and do not allow emergence near a working zone of naked flame or lamps without plafonds. Also do not work in a garage with the equipment on natural gas with a match. During any work with fuel system use goggles and you keep in readiness the fire extinguisher. At hit of fuel on skin, immediately wash away it water and soap.

Before starting service of fuel lines surely disconnect a negative wire from the battery and (on models with fuel injection) dump pressure in a power supply system (see the Section Removal of Pressure in system of injection of fuel).

Lines of giving and return of fuel, and also withdrawal of fuel evaporations pass from the fuel tank to a motive compartment of the car. Lines fasten to the car bottom clamps and screw assemblies. From time to time the line should check for existence of dents, twisting and other defects. Do not forget to pay also attention to a condition of short sections of the hoses inserted into the trunk fuel main - they are the most probable source of leaks (see an illustration).

At detection of signs of hit of dirt in a power supply system or in the fuel filter it is necessary to disconnect and blow fuel lines. On models with injection of fuel check also a condition of the mesh filter on the submersible fuel pump.

As fuel lines on models with fuel injection constantly are under high pressure, special requirements are imposed to them. When replacing rigid tubes use only company tubes of BMW. Do not establish plastic or copper sections at all - these materials are not capable to maintain the loadings connected with high pressures.