Fuel Return Line: Service and Repair
ENGINE COMPARTMENT FUEL LINES
Fuel Return Pipe To Engine:
Fuel Feed Pipe To Engine:
Fuel Feed And Return Pipes To Feed And Return Hoses:
WARNING:
^ To reduce the risk of fire and personal injury: DO NOT attempt to repair sections of nylon fuel lines. If damaged, replace.
^ DO NOT attempt to repair engine fuel feed or return pipes. If damaged, replace.
^ If nylon fuel feed or return lines become kinked, and cannot be straightened, they must be replaced.
REMOVAL:
Tools required: J 37088-A tool set, Fuel line quick-connect fittings.
1. Relieve the fuel system pressure, refer to MAINTENANCE PROCEDURES/FUEL SYSTEM PRESSURE RELIEF.
2. Disconnect the quick-connect fittings on the engine compartment fuel feed and return lines:
a. Grasp both ends of one fuel line connection and twist 1/4 turn in each direction to loosen any dirt in the quick-connect fitting. Repeat for other fittings.
WARNING: Safety glasses must be worn when using compressed air, as flying dirt particles may cause eye injury.
^ Using compressed air, blow out dirt from all quick-connect fittings before removing.
b. Choose the correct tool from the J 37088-A tool set for the size of the fitting.
c. Insert the tool into the female connector, then push inward to release the male connector.
d. Repeat for the other fitting.
3. Plug the fuel feed and return lines as required.
NOTE: If it is necessary to remove rust or burrs from the male tube end of a quick-connect fitting:
^ Use emery cloth in a radial motion with the tube end to prevent damage to the O-ring sealing surface.
^ Using a clean shop towel, wipe off the male tube ends.
^ Inspect all connectors for dirt or burrs. Clean or replace components/assemblies as required.
4. Remove the air duct from the throttle body.
5. Remove the engine fuel feed and return pipes mounting clamp and attaching screw.
^ Clean all engine fuel pipe connections and surrounding areas before disconnecting to avoid possible contamination of the fuel system.
6. Remove the engine fuel feed pipe from the regulator. Discard the O-ring.
7. Remove the engine fuel return pipe from the fuel rail. Discard the O-ring.
INSTALLATION:
1. Install new O-rings on the front fuel feed and return pipes.
2. Install the fuel feed and return pipes.
^ Use a back-up wrench on the fuel rail inlet fitting to prevent it from turning.
3. Install the engine fuel feed and return pipes mounting clamp and attaching screw.
4. Install the air inlet duct to the throttle body.
WARNING: To reduce the risk of fire and personal injury: Before connecting fuel line fittings, apply a few drops of clean engine oil to the male tube ends. This will ensure proper reconnection and prevent possible fuel leaks. (During normal operation, the O-rings located in the female connector will swell and may prevent proper reconnection if not lubricated).
5. Apply a few drops of clean engine oil to the male tube ends of the fuel feed and return lines.
6. Connect the fuel line quick-connect fittings:
a. Push the connectors together to cause the retaining tabs/fingers to snap into place.
b. Once installed, pull on both ends of each connection to make sure they are secure.
7. Tighten the fuel filler cap.
8. Connect the negative battery cable.
9. Turn the ignition switch to ON for two seconds, then turn it to the OFF position for ten seconds. Again turn the ignition switch to the ON position and check for fuel leaks.
FUEL VAPOR LINES AND HOSES
NOTE:
^ DO NOT attempt to repair fuel vapor lines or connecting hoses. If damaged, replace.
^ If nylon fuel feed and return lines become kinked, and cannot be straightened, they must be replaced.
^ When replacing vapor line connecting hoses, always replace them with original equipment or parts meeting GM specifications. Use only reinforced fuel-resistant hose which is identified with the word "Fluroelastomer" or "GM 6163-M" on the hose. The inside diameter must match outside pipe and line diameters.
REMOVAL:
1. Remove the hardware retaining the section of line to be replaced.
^ Note the location of the attaching hardware for installation.
2. Remove the section of line, hoses and clamps.
^ Check the hoses for cuts, swelling, cracks and distortion. Replace as required.
^ Check the lines for bends, kinks and cracks. Replace the sections as required.
INSTALLATION:
1. Follow the same routing as the original lines and hoses.
2. Hoses, clamps and lines must be properly secured to prevent chafing.
3. Reverse the removal procedure.