NGK LFR5A-11 Spark Plug (Stock 6376) - Standard Copper Core for Mercury, Mariner, Yamaha, Suzuki Outboards

The NGK LFR5A-11 is a standard spark plug identified by NGK stock number 6376, built around a solid copper core for strong heat dissipation, reliable conductivity, and a broad operating heat range. The shell carries a corrosion-resistant plating that keeps installation and removal easy even after the plug has seen heat cycling and marine or automotive service conditions. NGK Standard plugs like the LFR5A-11 are an OE cornerstone design, meaning they are built to the same baseline NGK has supplied to original equipment manufacturers for decades rather than a premium iridium or platinum upgrade.

The LFR5A-11 uses a standard ground configuration with a nickel ground electrode, a copper core center electrode, and a nickel center electrode tip. Electrical resistance is rated at 5000 ohms, which helps suppress ignition noise. This plug is listed to fit Infiniti model years 2010-01, Nissan model years 2008-00, and Suzuki model years 2011-09, and it also covers outboard motor applications, including Mariner model year 2000, Mercury model years 2006-00, and Yamaha model years 2005-99. Always confirm the correct spark plug against your engine's own maintenance manual before ordering, since installing the wrong plug can reduce fuel economy, cut performance, or damage the engine.

Specifications

• Brand: NGK
• Manufacturer Part Number: LFR5A-11
• Stock Number: 6376
• Resistance: 5000 ohms
• Ground Configuration: Standard
• Ground Electrode Core Material: Nickel
• Center Electrode Core Material: Copper
• Center Electrode Tip Material: Nickel
• Thread Size: 14 millimeters
• Weight: 0.15 pounds
• UPC: 087295163764

Fitment

• Infiniti, model years 2010-01
• Nissan, model years 2008-00
• Suzuki, model years 2011-09
• Mariner outboard, model year 2000
• Mercury outboard, model years 2006-00
• Yamaha outboard, model years 2005-99

Frequently Asked Questions

What is the NGK LFR5A-11 spark plug used for? The NGK LFR5A-11, NGK stock number 6376, is a standard spark plug with a solid copper core designed for reliable ignition performance across a broad heat range in applications such as Mercury, Mariner, Yamaha, and Suzuki outboard engines as well as certain Infiniti and Nissan applications.

What electrode materials does the LFR5A-11 use? This plug has a nickel ground electrode, a copper core center electrode, and a nickel center electrode tip, which is the standard NGK electrode configuration for this stock number 6376 plug.

What is the electrical resistance of NGK stock number 6376? The NGK LFR5A-11 (stock number 6376) is rated at 5000 ohms of resistance, which helps suppress ignition noise during operation.

What is the thread size of the NGK LFR5A-11? The thread size on this spark plug is 14 millimeters.

Does the NGK LFR5A-11 fit Mercury outboard engines? Yes, the LFR5A-11 (stock number 6376) is listed to fit Mercury outboard engines for model years 2006-00.

Is this spark plug compatible with Yamaha outboards? Yes, NGK lists the LFR5A-11 as fitting Yamaha outboard applications for model years 2005-99.

Does the LFR5A-11 fit Mariner outboards? It is listed for Mariner outboard model year 2000, in addition to its Mercury and Yamaha outboard coverage.

What ground electrode configuration does this plug have? The NGK LFR5A-11 uses a standard ground configuration, as opposed to a surface-discharge or semi-surface-discharge design found on some other NGK stock numbers.

Is the NGK LFR5A-11 a copper or iridium spark plug? It is a standard copper-core plug with a nickel-tipped center electrode, not an iridium or platinum design.

What is the weight of NGK stock number 6376? The NGK LFR5A-11 spark plug weighs 0.15 pounds.

Does this spark plug fit Suzuki, Nissan, or Infiniti models? Yes, the LFR5A-11 is listed for Suzuki model years 2011-09, Nissan model years 2008-00, and Infiniti model years 2010-01.

How do I know if the LFR5A-11 is the correct plug for my engine? Check your engine's own maintenance manual to confirm the correct spark plug, since using the wrong plug in place of the NGK LFR5A-11 (stock number 6376) can reduce fuel economy, cut performance, or damage the engine.