Champion 857 Spark Plug

Reliable Ignition Performance for Jeep Wagoneer

The Champion Copper Plus 857 spark plug is engineered to deliver consistent ignition performance for your Jeep Wagoneer. Designed with durable nickel electrodes and a precise pre-gap, this spark plug supports efficient combustion and reliable engine starts.

• Ground electrode core made of nickel for durability
• Non-removable nut electrical terminal type
• Nickel center electrode tip for stable spark
• Pre-gap size of 0.025 inches (0.64 mm) for optimal ignition
• Flat seat type ensuring proper sealing
• Heat range rating of 18 for controlled temperature management
• Thread diameter of 14 mm (0.551 inches) with 0.438 inch reach
• Resistor type spark plug to reduce electrical noise
• Hex size of 20.65 mm (0.813 inches) for easy installation

About the Champion Copper Plus Product Line

The Copper Plus line from Champion focuses on spark plugs with copper cores and nickel electrodes, providing a balance of conductivity and durability. This line is designed to meet the ignition needs of small engine applications, such as those found in the Jeep Wagoneer, ensuring consistent spark delivery and engine efficiency.

Technical Details and Specifications

The Champion Copper Plus 857 spark plug features a single ground electrode constructed from nickel, paired with a nickel center electrode tip. The pre-gap is factory set at 0.025 inches (0.64 mm), which supports reliable ignition timing and combustion. Its flat seat design ensures a secure fit and proper sealing within the combustion chamber. The spark plug has a heat range of 18, suitable for managing engine temperatures in the Jeep Wagoneer. Additionally, the resistor type helps minimize electromagnetic interference with vehicle electronics. The thread diameter measures 14 mm with a reach of 0.438 inches, compatible with the specified engine design.

Applications and Problem Solving

• Compatible with Jeep Wagoneer ignition systems requiring part number 857
• Helps resolve misfires caused by worn or damaged spark plugs
• Improves cold starts and engine responsiveness
• Reduces fouling and carbon buildup in combustion chambers
• Supports stable engine idling and smooth acceleration

Installation Notes and Tips

When installing the Champion Copper Plus 857 spark plug, ensure the pre-gap is maintained at the factory setting of 0.025 inches (0.64 mm) if adjustment is necessary. Use a 20.65 mm (13/16 inch) socket wrench for proper torque application. Confirm the flat seat type matches the engine’s cylinder head design to avoid sealing issues. Always replace spark plugs in sets to maintain consistent engine performance.

Quality Assurance and Warranty

Champion spark plugs, including the Copper Plus 857, are manufactured to meet strict quality standards for durability and performance. The resistor design reduces electrical interference, contributing to reliable vehicle electronics operation. While specific warranty details may vary, Champion products typically come with manufacturer-backed quality assurance to support long-term use in compatible vehicles like the Jeep Wagoneer.