Tools You'll Need:
* Socket set (various sizes, including deep sockets)
* Wrenches (various sizes)
* Screwdrivers (Phillips and flathead)
* Fuel line disconnect tool (highly recommended to avoid damaging the lines)
* Drain pan
* Shop rags or paper towels
* Safety glasses
* Gloves
* New fuel sending unit (make sure you get the correct one for your year and tank type)
* Optional: Fuel tank straps (if yours are damaged or rusty)
* Optional: Torque wrench (for proper tightening of bolts)
Procedure:
1. Safety First: Disconnect the negative battery terminal. This prevents accidental sparks near flammable fuel vapors. Work in a well-ventilated area.
2. Fuel Tank Depressurization: Carefully relieve pressure in the fuel system. You can do this by running the engine until it stalls, or by disconnecting the fuel pump relay (consult your shop manual for location).
3. Drain the Fuel Tank: Carefully siphon or drain the fuel from the tank using a suitable pump. Pour the fuel into approved containers, taking all necessary precautions.
4. Access the Fuel Tank: This is the most challenging part, varying slightly depending on whether you have a drop tank or an in-tank sending unit. Generally, it involves:
* Drop Tank: You'll likely need to remove the fuel tank straps and lower the tank carefully. This may involve disconnecting the fuel lines and the filler neck. Support the tank to prevent it from dropping suddenly.
* In-Tank: Access might be through a hole in the trunk floor. Consult a shop manual to determine how to access the tank in your specific model.
5. Disconnect the Fuel Lines and Electrical Connector: Use the fuel line disconnect tool to safely separate the fuel lines from the sending unit. Carefully disconnect the electrical connector from the sending unit.
6. Remove the Old Sending Unit: This usually involves removing several bolts or a retaining ring securing the unit to the tank. Take note of how it's assembled for reinstallation.
7. Install the New Sending Unit: Carefully install the new sending unit, ensuring it's properly seated. Tighten the bolts or ring securely, but avoid over-tightening.
8. Reconnect the Fuel Lines and Electrical Connector: Connect the fuel lines and electrical connector securely. Double-check for leaks.
9. Reinstall the Fuel Tank: Carefully raise and secure the fuel tank back into its position. Replace any worn or damaged straps.
10. Reconnect Fuel Lines: Double check that all fuel lines are firmly and securely attached.
11. Reconnect the Battery: Reconnect the negative battery terminal.
12. Check for Leaks: Carefully inspect all fuel connections for leaks. Start the engine and check for leaks again.
13. Test the Gauge: Verify that the fuel gauge is working correctly. The needle should move smoothly across the full range of the gauge.
Important Considerations:
* Shop Manual: A shop manual specific to your '64-'65 Mustang is highly recommended. It provides detailed diagrams, torque specifications, and valuable guidance.
* Safety: Fuel is highly flammable. Take all necessary safety precautions. Work in a well-ventilated area and avoid sparks.
* Cleanliness: Keep the area clean to prevent debris from entering the fuel system.
* Fuel Type: Use the correct type of fuel for your vehicle.
If you are not comfortable performing this task yourself, it is best to take your car to a qualified mechanic. Improperly handling fuel lines or the fuel tank can be dangerous.
