Here's a general outline. Specific steps and locations might vary slightly depending on your exact truck model and trim. Consult a repair manual specific to your year and model for detailed diagrams and torque specifications. A Haynes or Chilton manual is a good investment.
1. Preparation:
* Safety First: Disconnect the negative battery terminal.
* Gather Tools: You'll need socket wrenches (various sizes), a fuel pump removal tool (often a special socket), jack stands (essential!), jack, screwdrivers (Phillips and flathead), wrenches, pliers, rags, safety glasses, gloves, and a fuel line disconnect tool. A fuel pressure gauge is helpful but not strictly necessary.
* Drain the Fuel Tank: This is crucial to minimize fuel spillage. You can siphon the gas out using a siphon pump.
* Locate the Fuel Pump: It's usually accessed from under the truck, near the fuel tank. Consult your repair manual for the exact location.
2. Accessing the Fuel Pump:
* Raise the Truck: Safely jack up the rear of the truck and secure it on jack stands.
* Remove Access Panel/Cover: There's usually an access panel under the truck bed specifically designed for fuel pump access. You might need to remove some bolts or clips. Consult your manual.
* Disconnect Fuel Lines: Use the fuel line disconnect tool to carefully separate the fuel lines from the pump. Be prepared for some fuel spillage, even after draining the tank. Have rags ready.
* Disconnect Electrical Connections: Unplug the electrical connector to the fuel pump.
3. Removing the Fuel Pump:
* Remove the Fuel Pump: This is where the special fuel pump removal tool comes in handy. It helps you grip and remove the pump from the tank without damaging it. Some pumps are held in place by a retaining ring. The removal procedure will vary depending on the design. Your repair manual will guide you here.
* Inspect the Fuel Pump and Strainer: Carefully inspect the old fuel pump and fuel strainer for any damage or debris. Replace both if necessary.
4. Installing the New Fuel Pump:
* Install New Fuel Strainer (If Needed): Make sure the new strainer is correctly seated.
* Install the New Fuel Pump: Carefully lower the new fuel pump into the tank, ensuring it's seated correctly. Use the removal tool in reverse to secure it.
* Reconnect Electrical Connections: Plug in the electrical connector to the new pump.
* Reconnect Fuel Lines: Carefully reconnect the fuel lines, making sure they're securely attached.
5. Final Steps:
* Lower the Truck: Carefully lower the truck from the jack stands.
* Reconnect Battery: Reconnect the negative battery terminal.
* Check for Leaks: Inspect all connections for leaks.
* Start the Engine: Start the engine and listen for any unusual noises or leaks. Let the engine run for a few minutes to check for fuel pressure.
* Drive and Monitor: Take the truck for a short drive and monitor for any performance issues.
Important Considerations:
* Fuel Pressure: A fuel pressure gauge can help ensure proper fuel pressure after installation. Your repair manual should specify the correct pressure.
* Safety Precautions: Gasoline is highly flammable. Work in a well-ventilated area, away from any ignition sources. Use proper safety equipment.
* Repair Manual: Investing in a repair manual specific to your 1990 Chevy truck is highly recommended. It will provide detailed instructions, diagrams, and torque specifications.
This is a general guide. Always refer to a repair manual for your specific vehicle model for precise instructions and safety precautions. If you're uncomfortable performing this repair yourself, it's best to take your truck to a qualified mechanic.
