1. Preparation:
* Safety First: Disconnect the negative battery cable. This prevents accidental sparks. Work in a well-ventilated area away from open flames.
* Gather Tools: You'll need a variety of tools, including wrenches (metric), sockets, ratchets, a fuel line disconnect tool (important!), jack stands, jack, safety glasses, gloves, and potentially a fuel tank strap wrench.
* Consult a Repair Manual: A Haynes or Chilton repair manual specific to your 1989 S10 Blazer 4WD is invaluable. It will provide detailed diagrams and torque specifications.
2. Accessing the Fuel Tank:
* Raise the Vehicle: Safely lift the Blazer using a jack and secure it on jack stands. Never work under a vehicle supported only by a jack.
* Remove the Plastic Shield (if necessary): This usually involves removing a few screws or bolts holding it in place. The exact method depends on the specific design of your shield.
* Locate Fuel Lines and Electrical Connections: Identify the fuel lines (supply and return), vent line, and the fuel level sender wire(s).
3. Disconnecting Fuel Lines and Electrical Connections:
* Fuel Lines: This is crucial. Use the fuel line disconnect tool to carefully separate the lines from the tank. Have rags or shop towels ready to absorb any spilled fuel. Consider using fuel line clamps to prevent accidental disconnections later.
* Vent Line: Disconnect the vent line.
* Electrical Connections: Unplug the fuel level sender connector.
4. Removing the Fuel Tank:
* Release the Straps: The fuel tank is secured by straps. These straps may have bolts or clips. Loosen and remove the straps. A fuel tank strap wrench can make this easier.
* Lower the Tank: Carefully lower the fuel tank. It's usually heavy and contains some residual fuel, so be prepared for its weight. Have a helper if possible.
* Note: There might be some additional components attached to the tank (like the fuel pump assembly) that need to be disconnected before you can completely remove the tank.
5. Post-Removal:
* Secure the Tank: Carefully support the fuel tank to prevent damage.
* Clean Up: Clean up any spilled fuel immediately.
Important Considerations:
* Fuel Pump: The fuel pump is often integrated into the tank. You may need to remove the fuel pump assembly as part of removing the tank, or it may be necessary to replace the pump while you have access to it.
* Fuel System Pressure: The fuel system may still have some pressure. Releasing the pressure before disconnecting the lines is recommended (consult your repair manual).
* Environmental Concerns: Properly dispose of any spilled fuel. Do not pour fuel on the ground.
This is a general guide. The exact procedures and the specific tools required might vary slightly depending on the year and trim level of your S10 Blazer. Always consult a repair manual specific to your vehicle for precise instructions and safety precautions. If you're not comfortable performing this task yourself, it's best to take your Blazer to a qualified mechanic.
