Champion RN5C Marine Spark Plug (Champion 123) - Copper Core, 14mm Thread, Replaces Bombardier 507665

The Champion RN5C is a copper-core marine spark plug built as a quality OEM replacement for small marine and outboard engines. Also sold under Champion's own plug number 123, this spark plug uses a copper core center electrode that improves conductivity and gives accurate control over heat range, helping the plug resist fouling and wear over repeated heat cycles. Champion designs this plug to resist overheating under the sustained heavy loads typical of marine engine operation, and the shell and electrode materials provide superior corrosion resistance for the wet, salt-exposed environment a boat engine runs in.

The Champion RN5C/123 is commonly specified for Evinrude outboard engines and other small marine and utility engines that call for this plug, and it is built to ISO and SAE standards as an OE-type replacement. It ships as a single spark plug with a 14 millimeter thread, and it directly cross-references to OEM plug numbers used by Bombardier and Kubota, making it a straightforward replacement when your engine manufacturer specifies one of those part numbers instead of the Champion designation.

Specifications

• Brand: Champion
• Manufacturer Part Number: RN5C
• Champion Plug Number: 123
• Core Material: Copper
• Material: Copper
• Thread Size: 14 millimeters
• Unit Count: 1 spark plug (pack of 1)
• UPC: 037551000876
• Weight: 0.15 pounds
• Engine Service Type: Marine, small engine
• OEM Equivalent Part Numbers: Bombardier 507665, Kubota 12681-6774-1
• Warranty: Non-automotive spark plug guarantee - when installed per Champion recommendations, meets or exceeds the engine manufacturer's warranty requirements

Fitment

The Champion RN5C (Champion 123) is used in Evinrude outboard engines and other small marine engines that call for a Champion RN5C or Champion 123 spark plug with a 14 millimeter thread.

Replaces (OEM)

• Bombardier 507665
• Kubota 12681-6774-1

Frequently Asked Questions

What is the Champion RN5C spark plug? The Champion RN5C is a copper-core marine spark plug, also sold as Champion plug number 123, designed as an OE-type replacement for small marine and outboard engines.

Is Champion 123 the same spark plug as the RN5C? Yes, Champion 123 and Champion RN5C are the same copper-core marine spark plug; 123 is Champion's own plug number for the RN5C.

What engines is the Champion RN5C spark plug used in? This plug is commonly used in Evinrude outboard engines and other small marine engines that call for a Champion RN5C or Champion 123 spark plug.

Does the Champion RN5C cross-reference to any other OEM part numbers? Yes, the Champion RN5C (Champion 123) cross-references to Bombardier part number 507665 and Kubota part number 12681-6774-1.

What is the thread size on the Champion RN5C spark plug? 14 millimeters is the thread size of the Champion RN5C (Champion 123) spark plug.

What electrode material does the Champion RN5C use? A copper core center electrode is used in the Champion RN5C, which improves conductivity and allows accurate control of heat range for longer wear life.

How many spark plugs come in a package? One Champion RN5C (Champion 123) spark plug ships per pack.

How much does the Champion RN5C spark plug weigh? 0.15 pounds is the weight of the Champion RN5C (Champion 123) spark plug.

Is the Champion RN5C a genuine Champion part or an aftermarket copy? The Champion RN5C (Champion 123) is a genuine Champion spark plug, not a third-party aftermarket copy.

Does the Champion RN5C resist corrosion and fouling? Yes, the Champion RN5C is built with superior corrosion resistance and is designed to resist fouling under heavy marine engine loads.

Is the Champion RN5C covered by a warranty? Champion backs the RN5C (Champion 123) with a non-automotive spark plug guarantee; when installed per Champion's recommendations, it meets or exceeds the engine manufacturer's warranty requirements.

How does the Champion RN5C differ from Champion's Copper Plus RN9YC or RS9YC plugs? The Champion RN5C is a standard copper-core plug, while Champion's RN9YC and RS9YC are Copper Plus plugs that add TinTac and ULTRASEAL shell coating plus a SAC-9 semiconductor for extra corrosion resistance and EMI/RFI suppression; the RN5C does not include those added coatings.