Here's a general overview of the process. This is NOT a complete guide and should not be used as a substitute for a proper repair manual. Improperly performing this repair can lead to injury or further damage to your vehicle.
Preliminary Steps:
1. Safety First: Disconnect the negative battery terminal. This prevents electrical shocks and potential short circuits.
2. Gather Tools and Supplies: You'll need a variety of tools, including wrenches (various sizes), sockets, screwdrivers, pliers, a fuel pump removal tool (often specialized), jack stands, jack, safety glasses, gloves, and possibly a fuel line disconnect tool. A new fuel pump, fuel filter, and possibly gaskets are also necessary.
3. Fuel System Pressure Relief: There's pressure in the fuel lines. Consult your repair manual for the proper procedure to relieve this pressure. This is crucial to prevent fuel spray and fire hazard.
General Steps (highly simplified and may vary):
1. Access the Fuel Pump: This usually involves dropping the fuel tank. This requires careful jacking and securing the vehicle on jack stands. You'll likely need to disconnect the fuel tank straps and fuel lines. Some models might allow access from the trunk (rare on '81 Cadillacs, but check).
2. Disconnect Fuel Lines and Electrical Connections: Carefully disconnect the fuel lines from the fuel pump. Have rags ready to absorb any spilled fuel. Disconnect the electrical connector to the pump.
3. Remove the Fuel Pump: This is where the specialized tool often comes in. It's designed to securely grip the pump and remove it from the tank. The pump might be accessed through a circular access panel on top of the fuel tank or it might be part of a fuel pump assembly within the fuel tank.
4. Install the New Fuel Pump: Carefully install the new fuel pump, ensuring a proper seal. Use new gaskets if required.
5. Reconnect Everything: Reconnect the fuel lines, electrical connector, and fuel tank straps.
6. Lower the Fuel Tank: Carefully lower the fuel tank back into its position.
7. Reconnect the Battery: Reconnect the negative battery terminal.
8. Check for Leaks: Before starting the vehicle, check all connections for leaks.
9. Start the Vehicle: Start the vehicle and check for proper operation.
Important Considerations:
* Fuel Tank Removal: Dropping the fuel tank is a significant part of this job. Be extremely careful and follow all safety procedures.
* Fuel Spillage: Avoid spilling fuel. It's flammable and harmful to the environment.
* Proper Torque: Use the correct torque specifications for all bolts and fasteners. Over-tightening can damage components.
* Air in the Fuel System: After reinstalling the pump, there might be air in the fuel lines. You might need to crank the engine several times to purge the air.
Disclaimer: This is a simplified overview. It is crucial to consult a repair manual specific to your 1981 Cadillac DeVille for detailed, accurate instructions and safety precautions. Improperly performing this repair can be dangerous and lead to damage to your vehicle. If you are not comfortable performing this repair yourself, take your vehicle to a qualified mechanic.
