See Figure 1
The fuel pump with a damper is located in the fuel tank. The vane rollers are directly coupled to the motor which is cooled by fuel. a relief valve in the pump is designed to open at 44-64 psi, should a malfunction arise.
REMOVAL & INSTALLATION
- Before disconnecting the fuel lines or any of the fuel system components, refer to Fuel Pressure Release procedures and release the fuel pressure.
- Disconnect the negative battery cable. Disconnect the fuel gauge electrical connector and remove the fuel tank inspection cover.
If the truck has no fuel tank inspection cover the fuel tank must be lowered or removed to gain access to the in-tank fuel pump.
- Disconnect the fuel outlet and the return hoses. Remove the fuel tank if necessary.
- Remove the ring retaining bolts and the O-ring, then lift the fuel pump assembly from the fuel tank. Plug the opening with a clean rag to prevent dirt from entering the system.
When removing or installing the fuel pump assembly, be careful not to damage or deform it. Always install a new O-ring.
- Install the fuel pump assembly in the fuel tank with a NEW O-ring. Install the ring retaining bolts. Install the fuel tank if removed.
- Reconnect the fuel lines and the electrical connection.
- Connect battery cable, start engine and check for fuel leaks.
On some late models the "Check Engine Light" will stay on after installation is completed. The memory code in the control unit must be erased. To erase the code disconnect the battery cable for 10 seconds then reconnect after installation of fuel pump.
See Figure 2
- Release the fuel pressure. Connect a fuel pressure gauge between the fuel filter outlet and fuel feed pipe.
- Start the engine and check that the pressure is approximately 37 psi.
Make sure that the fuel filter is not blocked before replacing any fuel system components.
- If pressure is not as specified, replace the pressure regulator and repeat the test. If the pressure is still incorrect, check for clogged or deformed fuel lines, then replace the fuel pump.