The 1973-1987 Chevy trucks, often referred to as "squarebody" trucks, are popular among enthusiasts for their classic design and robust performance. This guide provides an overview of the fuel line setup for these vehicles, focusing on dual tank configurations. Whether you're restoring a truck or performing maintenance, understanding the fuel line diagram is crucial for ensuring proper fuel delivery.

Overview of Fuel Line System

The fuel system in 73-87 Chevy trucks typically includes two tanks, a fuel selector valve, and lines that connect to the engine. The configuration can vary based on the specific model and engine type, but the basic components remain consistent across most dual tank setups.

Key Components

  • Fuel Tanks: Usually located on either side of the truck.
  • Fuel Selector Valve: Directs fuel from the selected tank to the engine.
  • Fuel Lines: Includes supply lines, return lines, and vent lines.

Fuel Line Diagram Explanation

The fuel line diagram for a 73-87 Chevy truck with dual tanks generally consists of the following connections:

ComponentConnection
Fuel Tank (Left)To Fuel Selector Valve (Input)
Fuel Tank (Right)To Fuel Selector Valve (Input)
Fuel Selector ValveTo Engine (Output)
Fuel PumpFrom Selector Valve (Supply)
Return LineFrom Engine to Selector Valve
Vent LinesFrom Tanks to Atmosphere

Important Notes

  • Fuel Line Sizes: Common sizes include 3/8" for supply lines and 5/16" for return lines. Ensure that you use appropriate sizes to prevent issues with fuel flow and pressure.

  • Selector Valve Position: The selector valve is typically located between the two tanks. It has multiple ports for connecting the input from each tank and output to the engine.

Installation Tips

When installing or replacing fuel lines in a 73-87 Chevy truck, consider the following tips:

  • Use Quality Materials: Opt for fuel lines made from durable materials like Galfan® coated steel or stainless steel braided Teflon to prevent rust and leaks.

  • Secure Connections: Ensure all connections are tight and leak-free. Use appropriate clamps and fittings designed for fuel systems.

  • Check Compatibility: If you are modifying your truck with new engines or components (like LS swaps), verify that all parts are compatible with your existing setup.

FAQs About Fuel Lines in 73-87 Chevy Trucks

    • What size fuel line do I need?
      The typical supply line size is 3/8", while return lines are usually 5/16". Always check your specific model requirements.

    • How do I troubleshoot fuel delivery issues?
      Check for clogs in the lines, ensure the selector valve is functioning properly, and verify that the fuel pump is operational.

    • Can I upgrade my fuel system?
      Yes, many enthusiasts upgrade to EFI systems or LS swaps. Ensure you have compatible parts and follow appropriate installation procedures.

Understanding the fuel line diagram and setup for your 73-87 Chevy truck will help ensure reliable operation and performance. Proper installation and maintenance of these components are essential for enjoying your classic vehicle.