Here's a general outline. This is NOT a complete, step-by-step guide and should not be considered a substitute for a professional repair manual specific to your Blazer's engine and trim level. Consult a repair manual for detailed instructions, torque specifications, and diagrams relevant to your specific vehicle. Improper procedures can lead to damage or injury.
1. Preparation:
* Safety First: Disconnect the negative battery cable.
* Gather Tools: You'll need jack stands, jack, wrenches (various sizes), sockets, ratchet, fuel line disconnect tools, a fuel pump pliers or wrench (possibly a special tool depending on the pump design), safety glasses, gloves, rags, and potentially a new fuel filter. A fuel pressure gauge can also be helpful to ensure the system is properly depressurized.
* Locate the Fuel Pump: Usually located inside the fuel tank, under the vehicle. Your repair manual will show the exact location.
* Drain the Fuel Tank (Highly Recommended): Siphoning out as much fuel as possible will greatly reduce the amount of fuel you'll be working around and the risk of spillage.
2. Accessing the Fuel Pump:
* Lower the Fuel Tank (Usually Necessary): This is the most labor-intensive part. You'll likely need to:
* Support the vehicle securely with jack stands.
* Remove the rear seats (if necessary for access).
* Disconnect the fuel filler neck.
* Disconnect the fuel lines (carefully). Use fuel line disconnect tools to avoid damaging the lines.
* Disconnect the fuel tank sending unit electrical connector.
* Possibly disconnect the fuel tank straps.
* Carefully lower the fuel tank using a jack or jacking straps, supporting its weight. Be extremely careful; the tank is heavy and contains fuel.
* Alternative Access (Less Common): Some models may allow access through a dedicated access panel in the bed or under the vehicle. Check your repair manual for this possibility.
3. Replacing the Fuel Pump:
* Remove the Fuel Pump Assembly: This involves removing the retaining bolts or ring holding the pump in place.
* Remove the Old Fuel Pump: This often involves carefully detaching the electrical connector and fuel lines from the old pump.
* Install the New Fuel Pump: Carefully install the new pump, ensuring it's properly seated and all connections are secure.
* Reinstall the Fuel Pump Assembly: Reverse the removal procedure.
4. Reassembly:
* Raise the Fuel Tank (if lowered): Carefully raise the fuel tank back into place and reconnect all lines and straps. Ensure all connections are secure and tight.
* Reconnect Electrical Components: Ensure all electrical connectors are securely connected.
* Reconnect Fuel Lines: Again, use the proper tools to avoid damage.
* Reconnect Battery Cable: Re-connect the negative battery cable.
* Check for Leaks: Check all connections for fuel leaks.
* Prime the Fuel System (Important): This may involve turning the ignition key to the "on" position for a few seconds (without starting the engine) to allow the fuel pump to prime.
* Start the Engine and Check for Proper Operation: After starting the engine, listen for the fuel pump's whirring sound.
Important Considerations:
* Fuel Pressure: Use a fuel pressure gauge to test fuel pressure after the installation to verify correct function.
* Repair Manual: This is absolutely essential. A Haynes or Chilton manual specific to your 1992 Chevrolet Blazer will provide detailed diagrams and step-by-step instructions crucial for successful completion.
* Professional Help: If you are uncomfortable with any part of this process, consider seeking professional help from a qualified mechanic.
Remember, safety is your top priority. Working with gasoline is dangerous. If you're not comfortable performing this repair, take your vehicle to a qualified mechanic. This information is for guidance only and doesn't replace a professional repair manual or qualified mechanical assistance.
