Autolite 766 Spark Plug

Overview of Autolite Copper Resistor Spark Plug 766

The Autolite Copper Resistor Spark Plug 766 is engineered for reliable ignition performance in select Ford and Mercury vehicles. Designed with a copper core and resistor technology, this spark plug supports efficient combustion and consistent engine operation.

• Resistance: 5000 ohms for noise suppression
• Ground Electrode Tip: Tapered nickel design
• Center Electrode Core: Copper with nickel tip
• Electrical Terminal Type: Stud
• Pre-Gap Size: 0.044 inches (1.10 mm)
• Hex Size: 16 mm (5/8 inch)
• Thread Diameter: 14.0 mm
• Reach: 0.679 inches (17.0 mm)
• Seat Type: Tapered
• Insulator Material: Ceramic with mid projection
• Ground Electrode Quantity: 1

About the Copper Resistor Spark Plug Line

The Autolite Copper Resistor Spark Plug line combines copper core electrodes with resistor technology to reduce radio frequency interference while maintaining strong spark energy. This balance supports smooth ignition and engine efficiency, making it suitable for various Ford and Mercury models requiring a standard electrode design and tapered seat.

Technical Details and Compatibility

The Autolite 766 spark plug features a copper center electrode core for enhanced thermal conductivity and durability, paired with a nickel tip for wear resistance. The single tapered ground electrode, also nickel, ensures consistent spark gap integrity. With a 5000 ohm resistor, this plug minimizes electrical noise that can affect vehicle electronics. The ceramic insulator with mid projection supports stable voltage insulation and heat dissipation. This spark plug is compatible with Ford and Mercury vehicles including the Capri, Cougar, F-100, LTD, Marquis, Mustang, and Thunderbird models.

Common Applications and Problem Solving

• Improves ignition reliability in Ford Mustang and Mercury Cougar engines
• Reduces radio frequency interference affecting onboard electronics
• Maintains consistent spark gap for smoother engine starts
• Helps prevent misfires caused by electrode wear or corrosion
• Supports efficient combustion in classic Ford F-100 and Thunderbird models

Installation Notes and Tips

• Verify correct spark plug gap of 0.044 inches (1.10 mm) before installation
• Use a 16 mm (5/8 inch) socket for proper torque application
• Ensure tapered seat matches engine specifications for proper sealing
• Apply anti-seize compound sparingly on threads if recommended by vehicle manufacturer
• Torque to manufacturer’s specifications to avoid damage to threads or insulator

Quality Assurance and Warranty

Autolite spark plugs are manufactured to meet OEM standards for fit, form, and function. The Copper Resistor Spark Plug 766 undergoes rigorous quality control to ensure consistent resistance and electrode integrity. While specific warranty details vary by distributor, Autolite products typically include coverage against manufacturing defects. Consult product documentation or supplier for warranty terms.