Here's a general outline. Specifics will depend on your exact Suburban model (1/2 ton, 3/4 ton, etc.) and engine type. Consult a repair manual specific to your year and model for detailed instructions and diagrams. A Haynes or Chilton manual is a good investment.
1. Preparation:
* Gather Tools: You'll need jack stands, a socket set (including metric and standard), wrenches, screwdrivers, a fuel pump pliers or similar tool for fuel line disconnect, safety glasses, gloves, rags, a fuel pump installation kit (often includes seals and gaskets), and possibly a fuel pressure gauge.
* Safety Precautions: Disconnect the negative battery terminal. Ventilate the area well. Avoid sparks or open flames.
* Drain the Tank (Ideally): This is highly recommended to reduce the amount of fuel you're working around. You can siphon the fuel out using a siphon pump. Be extremely careful handling gasoline.
2. Accessing the Fuel Pump:
* Lower the Fuel Tank: This is usually the most challenging part. You'll likely need to:
* Support the tank with jack stands.
* Disconnect the fuel lines (carefully!). Use a fuel line disconnect tool to prevent damage to the lines. Have rags ready to soak up any spilled fuel.
* Disconnect the fuel tank sending unit electrical connector.
* Disconnect the tank straps.
* Lower the fuel tank carefully.
* Access the Pump: The fuel pump is usually located within the fuel tank. You'll need to remove the fuel pump access panel or cover on the top of the fuel tank. This often involves removing some bolts or clips.
3. Replacing the Fuel Pump:
* Remove the Old Pump: This will involve disconnecting electrical connectors and removing the pump assembly from the tank. Take note of the orientation and position of parts.
* Install the New Pump: Install the new fuel pump assembly, making sure to use all new gaskets and seals provided in your kit. Follow the instructions that came with your new fuel pump. Pay close attention to the orientation and how the old pump was installed.
* Reconnect Everything: Reassemble everything in reverse order of disassembly. Carefully reconnect the fuel lines, ensuring they are properly secured. Reconnect the electrical connectors and the tank straps.
4. Reinstallation and Testing:
* Raise the Fuel Tank: Carefully raise the fuel tank back into its position, ensuring all connections are secure.
* Reconnect the Battery: Reconnect the negative battery terminal.
* Check for Leaks: Inspect all fuel lines and connections for leaks.
* Start the Engine: Start the engine and listen for any unusual noises from the fuel pump. Check for leaks again.
* Check Fuel Pressure (Optional): If you have a fuel pressure gauge, you can check the fuel pressure to ensure the new pump is functioning correctly. Consult your repair manual for the correct fuel pressure specifications.
Important Considerations:
* Fuel Pump Module: The fuel pump in your 1990 Suburban is likely part of a larger fuel pump module. This module contains the pump, sender unit, and other components. Replacing the entire module is often simpler than trying to replace just the pump itself.
* Professional Help: If you are not comfortable performing this repair, it's best to take your Suburban to a qualified mechanic. Incorrect installation can lead to serious safety hazards.
This is a general overview. Refer to a repair manual for your specific vehicle for detailed instructions and diagrams. Always prioritize safety and use caution when working with gasoline.
