Top 10 Best boat engine spark plugs in 2026

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• •Consult owners manual for proper part number identification and proper installation
• •Genuine Champion Spark Plugs
• •Please refer to list for compatibility
• •Champion copper plus small engine spark plugs feature a copper core electrode that provides increased conductivity and heat control while delivering good overall wear characteristics

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• •Sold in packs of 4

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• •4 pack NGK Standard 5531 Spark Plug
• •Genuine NGK Parts
• •Includes original packaging and hardware
• •Direct replacement auto parts
• •Confirm vehicle fitment with Amazon Confirmed Fit

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• •NGK V-Power plugs feature a unique v-cut in the center electrode that directs the spark to the edge of the electrode, helping the spark develop more rapidly, increasing ignitability and reducing quenching
• •Brand new
• •NGK Spark Plugs

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• •NGK BU8H surface gap plugs feature a semi-surface discharge design to improve ignition and burn off any carbon before it can build up to foul the plug
• •Check your engine owner’s manual for the correct spark plug and use only the plug as recommended by your engine’s original equipment manufacturer
• •NGK Trivalent metal plating also provides superior anti-corrosion in the marine environment and anti-seizing for easier removal
• •Spark plugs are easy to change with common spark plug sockets
• •Spark plugs are easy to change with common spark plug sockets.

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• •【Compatibility Information】：Universal Spark Plug 4838 compatible with Mercury Mariner 125 hp 115 hp 100 hp 80 hp 60 hp 55 hp 50 hp 45 hp 40 hp 30 hp 25 hp 20 hp 18 hp 15 hp 9.9 hp 8.0 hp 6.0 hp Marathon etc.Please see images or details page for complete Compatibility information
• •【Spark Plug Features】:BDFHYK Spark plugs with superior ignition performance, faster and more sensitive ignition jumps, significant increase in power performance, saving energy consumption in the ignition process, efficiently adapted to the needs of the car. Exquisite production process, 100% brand new high quality auto parts, OE level durability
• •【Relive Performance】:OE standard performance and durability TS16949 certified manufacturer. All center electrodes are made from extremely fine iridium electrodes for good ignition performance. Insulators are made from isostatic ceramics for high density, strength, and good insulation
• •【OE Part Numbers】:Spark Plug compatible to 4838 BP8H-N-10.Please confirm the compatibility according to the year/make/model of your vehicle and the OE number of the replaceable part
• •【About BDFHYK】A professional auto parts manufacturer with mature industry lines. We have our factory and experienced developer.We are committed to providing a 12-month quality guarantee service. If you have any questions,contact with us,we will reply you in 24 hours and offer the solve way for you.Choose BDFHYK,choose good service

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• •Made by AC Delco with nickel alloy tip, copper core and ribbed suppressor seal for durability and performance
• •Check your engine owner’s manual for the correct spark plug and use only the plug as recommended by your engine’s original equipment manufacturer
• •Nickel-chrome alloy sheathing on the ground and center electrodes help resist wear from spark erosion and the corrosive environment of the combustion chamber
• •Replace all the engine plugs at the same time

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• •【Perfect Fit】Spark plugs Compatible with Mercury Mariner 125 hp 115 hp 100 hp 80 hp 60 hp 55 hp 50 hp 45 hp 40 hp 30 hp 25 hp 20 hp 18 hp 15 hp 9.9 hp 8.0 hp 6.0 hp Marathon etc. For more information about the fit, please check the picture or detail page. Note: Please verify your vehicle's make, model, and engine size before purchasing to ensure compatibility.
• •【OE Replacement】Direct replacement for OE numbers 4838, BP8H-N-10. These spark plugs meet or exceed OEM standards for form, fit, and function. Made from high-temperature resistant materials, they withstand extreme thermal stress, ensuring durability and reliability.
• •【Pre-Gapped Spark Plug】Each spark plug is pre-gapped to 1.0mm (0.039''), ensuring optimal ignition performance and hassle-free installation. For additional specifications such as thread size, hex size, and reach, please refer to the product images for complete details.
• •【Iridium Design】Crafted with precious iridium metal, these spark plugs offer stronger ignition performance, faster cold starts. The wear-resistant design enhances fuel efficiency, reduces carbon buildup, and extends engine life. Ideal for use in automobiles, trucks, SUVs, motorcycles, marine engines, and industrial equipment, these spark plugs are engineered to maximize engine power and improve overall vehicle performance.
• •【Customer Service & Quality Assurance】At SYKRSS, we prioritize your satisfaction. If you encounter any issues with our iridium spark plugs, contact us directly, and we will respond within 48 hours. Backed by a 4-year repair and replacement service, our spark plugs are manufactured by a professional automotive component brand with a mature production line. Choose SYKRSS for high-quality, reliable performance, and exceptional customer support.