The fuel system in 1973-1987 Chevy trucks is a critical component that requires proper maintenance and occasional upgrades. This guide will cover the essential aspects of fuel lines for these classic trucks, including stock configurations, common issues, and upgrade options.

Fuel Line Basics

The fuel system in 73-87 Chevy trucks typically consists of:

  • Fuel tank
  • Fuel sending unit
  • Fuel lines (supply and return)
  • Fuel pump
  • Fuel filter
  • Carburetor or fuel injection system

The stock fuel lines are usually made of steel and run from the fuel tank to the engine compartment. They include a main supply line and, in some cases, a return line for fuel-injected models.

Common Fuel Line Issues

Over time, these trucks may experience fuel line problems:

  • Rust and corrosion
  • Leaks at connection points
  • Deterioration of rubber hoses
  • Clogged lines due to debris or old fuel

Regular inspection of fuel lines is crucial to prevent these issues and ensure safe operation of your Chevy truck.

Upgrading Fuel Lines

Many owners choose to upgrade their fuel lines, especially when:

  • Converting to fuel injection
  • Increasing engine performance
  • Replacing damaged original lines

Popular upgrade options include:

  • Stainless steel braided lines
  • PTFE (Teflon) lines
  • Pre-bent OEM-style replacement lines

When upgrading, ensure that the new lines are compatible with your truck's fuel system and any modifications you've made.

Installation Tips

If you're replacing or upgrading your fuel lines:

  • Use the correct size lines (typically 3/8" for supply, 5/16" for return)
  • Follow the original routing as closely as possible
  • Use proper fittings and clamps
  • Install a new fuel filter
  • Check for leaks after installation

Always prioritize safety when working with fuel systems. Work in a well-ventilated area and disconnect the battery before starting.

Dual Tank Systems

Many 73-87 Chevy trucks came equipped with dual fuel tanks. These systems require:

  • A fuel selector valve
  • Additional fuel lines
  • A more complex wiring setup

When working on dual tank systems, pay special attention to the selector valve and ensure proper routing of all fuel lines.

FAQs About 73-87 Chevy Truck Fuel Lines

    • Can I use rubber fuel lines instead of steel?
      While rubber lines can be used for short sections, it's generally recommended to use steel or specialized fuel-safe materials for the main runs.
    • How often should I replace my fuel lines?
      There's no set timeframe, but inspect them annually and replace at the first signs of wear, corrosion, or leaks.
    • Do I need to change my fuel lines if I'm doing an LS swap?
      Yes, an LS swap typically requires upgrading to fuel injection-compatible lines that can handle higher pressure.

By understanding and properly maintaining your 73-87 Chevy truck's fuel lines, you can ensure reliable performance and extend the life of your classic vehicle.