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Champion 518 Spark PlugOE Quality 60-Day Returns
Part #: 518

Champion 518 Spark Plug

Copper Plus
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Copper Plus
Fitment: Pierce-Arrow, Auburn, Lincoln, Willys, Studebaker, Marmon, Packard, Roosevelt, Stearns Knight, Windsor, Cunningham, Yellow Cab, Chevrolet, Dodge, Falcon Knight, Franklin, LaSalle, Nash, Oldsmobile, Reo, Rickenbacker, Westcott, Buick, and Velie, Model 845, Model 836A, Model 840A, Silver Arrow, Model 8-101, Model 8-101A, Model 8-105, Model KA, Model KB, Model 836, Knight Model 66E, Model 8-100, Model 8-100A, Model 53, Model 54, Commander Model 71, Dictator Model 62, President Model 91, Rockne Model 65, Rockne Model 75, Six Model 55, Knight Model 66D, Knight Model 95 Deluxe, Model 8-98, Model 8-98A, Model K, Roosevelt, Model 826, Model 833, Model 840, Model 41, Model 42, Model 43, Commander Model 70, Dictator Model 61, Dictator Model FC, President Model 80, President Model 90, Six Model 53, Six Model 54, Knight Model 66B, Model 6-87, Model L, Model A, Model B, Model C, Eight, Model H-8-90, Model J-8-90, Commander, Dictator, President FE, President FH, Knight Model 6-87, Knight Model 70B, Model 6-69, Series V-7, Series 68, Series 78, Model 125, Model 126, Model M-6-80, Model N-6-80, Commander Eight, Commander Six, President Eight, Knight Model 56, Knight Model 66A, Knight Model 70A, Whippet Model 96A, Whippet Model 98A, Model O-6, Capitol Truck, Victory Six, Model 12, Airman, Series 303, Series 75, Advanced, Special, Model 36, Model 81, Model F-6-85, Model H, Model J, President Six, Whippet Model 96, Whippet Model 98, Capitol, Series V-6, Model 11 B, E-75 Series, Little Marmon Series, Model 30-E, Model 80, Flying Cloud, Model 6-70, Model 8-80, Model 8-90, Model D-6-85, Model G-8, President, Whippet Model 93A, Model 11 A, Model D-74, Model 33, Six, Model 6-C, Model 6-S, Big Six, Special Six, Standard Six, Knight Model 66, Knight Model 70, Model 91, Model 92, Model 93, Superior, Model 10 C, Model 4, Model H-44, Model H-60, Knight Model 65, Series V-5, Model 10 B, Model 34, Four, and Light Six
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Reliable Ignition with Champion Copper Plus Spark Plug 518

The Champion Copper Plus 518 spark plug is engineered for consistent ignition performance in agricultural and other compatible vehicles. Designed with durable nickel and copper alloy materials, this spark plug supports efficient combustion and reliable engine starts.

  • Ground electrode core and center electrode tip made of nickel for durability
  • Pre-gap size of 0.025 inches (0.64 mm) optimized for ignition efficiency
  • Single ground electrode constructed from nickel copper alloy
  • Flat seat type with 0.75 inch reach and 0.875 inch (22.225 mm) thread diameter
  • Heat range rating of 18 suitable for specific engine requirements
  • Hex size of 0.938 inch (23.830 mm) for standard installation tools
  • Non-resistor type spark plug with a 0.125 inch center electrode diameter

Detailed Features and Specifications

The Champion Copper Plus 518 spark plug features a nickel ground electrode core and center electrode tip, providing a balance of conductivity and wear resistance. The single ground electrode is made from a nickel copper alloy, enhancing durability under high-temperature conditions. With a pre-gap size of 0.025 inches (0.64 mm), this spark plug is pre-set to optimize spark efficiency and combustion. The flat seat design ensures a secure fit in compatible engines, while the 0.75 inch reach and 0.875 inch (22.225 mm) thread diameter match specific engine configurations. The heat range of 18 is calibrated for agricultural engines requiring moderate heat dissipation. The plug type W18 and the absence of a resistor make it suitable for certain ignition systems. Installation is facilitated by the 0.938 inch (23.830 mm) hex size, compatible with common spark plug sockets.

About the Champion Copper Plus Product Line

The Copper Plus line by Champion focuses on spark plugs that combine copper core technology with durable electrode materials to support reliable ignition in agricultural and industrial engines. The Copper Plus 518 spark plug is part of this line, offering a nickel and copper alloy electrode design that balances conductivity and longevity. This product line is tailored to meet the demands of engines requiring consistent spark performance under varied operating conditions.

Applications and Problem Solving

  • Compatible with agricultural engines requiring a heat range 18 spark plug
  • Addresses issues related to inconsistent ignition and misfires
  • Helps reduce electrode wear in high-temperature environments
  • Suitable for engines needing a flat seat spark plug with specific thread dimensions
  • Supports improved combustion efficiency in compatible vehicle models

Installation Notes and Tips

Before installation, verify the spark plug gap is set to 0.025 inches (0.64 mm) as specified. Use a 0.938 inch (23.830 mm) hex socket for proper torque application. Ensure the flat seat matches the engine’s cylinder head design to prevent leaks. Avoid over-tightening to maintain thread integrity and prevent damage. This spark plug is designed for engines compatible with the W18 plug type and a heat range of 18.

Quality Assurance and Warranty

Champion Copper Plus spark plugs are manufactured to meet industry standards for ignition components. While specific warranty details for part number 518 are not provided, Champion products typically undergo rigorous quality control to ensure reliable performance. For warranty information, refer to Champion’s official documentation or authorized distributors.

BrandChampion
Part Number518
PositionCopper Plus
Center Electrode Diameter (Inch)0.125
Center Electrode Tip MaterialNickel
ClassificationChampion Agricultural Plugs
Ground Electrode Core MaterialNickel
Ground Electrode MaterialNickel Copper Alloy
Ground Electrode Quantity1
Hex Size0.938
Hex Size23.830
Hex TypeHex
Installed Height (Inch)2.57
Manufacturer Heat Range18
Plug TypeW18
Pre-Gap Size0.025
Pre-Gap Size0.64
Reach0.75
Resistor TypeNo
Seat TypeFlat
Taper Diameter (Inch)0.42
Thread Diameter0.875
Thread Diameter22.225

This part fits 0 vehicles. Search below:

YearMakeModelPositionNotes

* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

This part directly replaces or is cross-referenced with the following part numbers:

22COM2COML35COM3COM436719797L7LXA53AA53AC600RC1C77LGH44JA53JB43W18

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.

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