{"product_id":"ngk-bu8h-standard-spark-plug-fits-1978-1999-mariner-1978-2002-mercury-outboards","title":"NGK BU8H Standard Spark Plug - Fits 1978-1999 Mariner \u0026 1978-2002 Mercury Outboards","description":"\u003cp\u003eThe NGK BU8H is a Standard spark plug built for Mercury and Mariner outboard engines, cataloged by NGK under stock number 6431. It uses proven NGK Standard-plug technology: a copper-core center electrode for strong heat dissipation and reliable conductivity, paired with a nickel center electrode tip and a nickel Standard-configuration ground electrode. The shell and threads are corrosion-resistant plated, making installation and future removal easier and helping prevent seizing in a marine environment.\u003c\/p\u003e\u003cp\u003eAs an OE-cornerstone plug, the BU8H is designed to deliver consistent ignition performance over the plug's service life, supporting steady starting and running on the outboard powerheads it is built for. It carries a 1 ohm resistance rating and a ceramic insulator body for reliable spark energy transfer and heat handling.\u003c\/p\u003e\u003cp\u003eThis plug is fit for specific outboard applications, so confirm your engine and maintenance manual before ordering, and use only the plug your engine manufacturer recommends. Using the wrong plug can reduce performance and fuel economy or damage your engine.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e NGK\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number:\u003c\/strong\u003e BU8H\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNGK Stock Number:\u003c\/strong\u003e 6431\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eResistance:\u003c\/strong\u003e 1 ohm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGround Configuration:\u003c\/strong\u003e Standard\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGround Electrode Core Material:\u003c\/strong\u003e Nickel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCenter Electrode Core Material:\u003c\/strong\u003e Copper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCenter Electrode Tip Material:\u003c\/strong\u003e Nickel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsulator Material:\u003c\/strong\u003e Ceramic\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size:\u003c\/strong\u003e 14mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.15 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 087295164310\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnit Count:\u003c\/strong\u003e 1 spark plug\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eOutboard - Mariner, 1978-1999\u003c\/li\u003e\n\u003cli\u003eOutboard - Mercury, 1978-2002\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat engines does the NGK BU8H spark plug fit?\u003c\/strong\u003e The NGK BU8H, cataloged as stock number 6431, fits Mercury outboards from 1978 to 2002 and Mariner outboards from 1978 to 1999.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the BU8H a resistor spark plug?\u003c\/strong\u003e No, the NGK BU8H carries a resistance rating of 1 ohm, which is a standard, non-resistor ignition plug.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat electrode materials does the NGK BU8H use?\u003c\/strong\u003e The BU8H has a copper-core center electrode with a nickel tip, and a Standard-configuration ground electrode made of nickel.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the ground electrode configuration on the BU8H?\u003c\/strong\u003e The NGK BU8H uses a Standard ground electrode design, not a surface-discharge type.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the NGK BU8H spark plug weigh?\u003c\/strong\u003e The NGK BU8H weighs 0.15 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the thread size of the BU8H spark plug?\u003c\/strong\u003e 14mm is the thread size of the NGK BU8H spark plug.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is NGK stock number 6431?\u003c\/strong\u003e Stock number 6431 is NGK's catalog reference for the BU8H, a Standard spark plug built for Mercury and Mariner outboards.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the BU8H a genuine NGK plug or an aftermarket copy?\u003c\/strong\u003e The BU8H is a genuine NGK Standard spark plug, not an aftermarket substitute.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat insulator material is used in the BU8H?\u003c\/strong\u003e A ceramic insulator body is used in the NGK BU8H spark plug.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many spark plugs come with this listing?\u003c\/strong\u003e One NGK BU8H spark plug is included per unit.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the NGK BU8H spark plug?\u003c\/strong\u003e 087295164310 is the UPC for the NGK BU8H spark plug.\u003c\/p\u003e","brand":"NGK Spark Plugs","offers":[{"title":"Default Title","offer_id":49028254007515,"sku":"NGK-BU8H","price":4.66,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/NGK-BU8H__28795.1558187611.500.750.jpg?v=1785165230","url":"https:\/\/www.goodvibesmarina.com\/products\/ngk-bu8h-standard-spark-plug-fits-1978-1999-mariner-1978-2002-mercury-outboards","provider":"Good Vibes Marina","version":"1.0","type":"link"}