Here's a general outline of the process. Specific steps and challenges might vary slightly depending on your car's condition and any modifications:
1. Preparation:
* Safety First: Disconnect the negative battery cable.
* Gather Tools: You'll need various sockets (likely metric), wrenches, screwdrivers (Phillips and possibly flathead), a fuel pump pliers (or similar tool for fuel lines), a container to catch fuel, rags or shop towels, safety glasses, and possibly a fuel pressure gauge (to relieve pressure safely).
* Drain the Tank (Recommended but not always necessary): Siphoning or draining as much fuel as possible from the tank is highly recommended to minimize spillage. This makes the job much safer and cleaner.
2. Accessing the Sending Unit:
* Locate the Fuel Tank: It's usually located under the car, towards the rear.
* Access Panel: The 1979 Corvette likely has an access panel on the underside of the car specifically for the fuel tank and sending unit. This will involve removing bolts or fasteners. Consult your shop manual for the exact location.
* Remove Access Panel: Carefully remove the access panel.
3. Removing the Sending Unit:
* Disconnect Electrical Connections: Unplug the electrical connector from the fuel sending unit.
* Disconnect Fuel Lines: Use fuel line pliers (or similar) to carefully disconnect the fuel lines from the sending unit. Have your container ready to catch any remaining fuel. Note: Some fuel will likely escape.
* Remove the Sending Unit: The sending unit is typically held in place by a retaining ring or clamp, and sometimes bolts. This is where a shop manual becomes crucial. The method varies slightly depending on the exact type of sending unit in your car. You may need to carefully pry or turn the retaining ring to release it. Take pictures as you disassemble to help you remember how things go back together.
4. Removing the Unit (Continued):
* Resistance: You may encounter resistance from the sending unit's gasket or corrosion. Use penetrating oil (like PB Blaster) if needed to loosen things up before attempting to remove. Gently work the unit out. Force is not your friend here; you could damage the unit or the tank.
5. Reassembly (Reverse of Removal):
* Clean the Tank: If possible, clean any debris around the tank opening.
* Install New Gasket: It's highly recommended to replace the gasket on the sending unit before reinstalling.
* Install Sending Unit: Carefully insert the new (or cleaned) sending unit into the tank.
* Reconnect Fuel Lines & Electrical Connector: Make sure the connections are secure.
* Reinstall Access Panel: Secure the access panel.
* Reconnect Battery: Reconnect the negative battery cable.
Important Considerations:
* Shop Manual: A factory service manual specific to a 1979 Corvette is invaluable. It will provide detailed diagrams, torque specifications, and troubleshooting steps.
* Fuel Pump Pressure: Some fuel systems have a pressure regulator that must be relieved before working on the fuel system. A fuel pressure gauge can help ensure safety.
* Cleanliness: Keep everything clean to prevent contamination of the fuel system.
* New Parts: Consider replacing the gasket and any other worn parts while you have the sending unit out.
This is a general guide. Always consult a repair manual specific to your 1979 Corvette before starting any repair. If you are uncomfortable performing this repair yourself, take it to a qualified mechanic. Working with fuel systems requires caution and proper technique.
