{"product_id":"ngk-v-power-spark-plug-7558-zfr5f-equivalent-fits-mercury-efi-4-stroke-65-150-hp-outboards","title":"NGK V-Power Spark Plug 7558, ZFR5F Equivalent - Fits Mercury EFI 4-Stroke 65-150 HP Outboards","description":"\u003cp\u003eThe NGK 7558 is a V-Power spark plug engineered for reliable ignition and consistent performance in Mercury EFI 4-Stroke outboard engines from 65 HP to 150 HP. Built around NGK's ZFR5F design, this resistor plug pairs a copper center electrode core with a nickel ground electrode core to deliver strong, consistent sparking across the engine's operating range. The flat seat design and 14 mm x 1.25 mm thread ensure a precise, gas-tight fit in the cylinder head, while the 0.749 inch reach and 5\/8 inch hex size match factory specifications for straightforward installation with a standard spark plug socket.\u003c\/p\u003e\u003cp\u003eRated at 5000 Ohm resistance, the NGK 7558 helps suppress electrical interference that can affect onboard electronics while maintaining dependable ignition timing. The plug ships pre-gapped to 0.32 inches, so it is ready to install without additional adjustment on most applications. As a direct equivalent to Mercury part numbers 33-8M0204728 and 33-8M0057936, it is a straightforward replacement for boat owners servicing compatible Mercury EFI 4-Stroke outboards.\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 7558\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Line:\u003c\/strong\u003e NGK V-Power\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlug Type:\u003c\/strong\u003e ZFR5F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e Resistor\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size:\u003c\/strong\u003e 14 mm x 1.25 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReach:\u003c\/strong\u003e 0.749 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHex Size:\u003c\/strong\u003e 5\/8 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeat Type:\u003c\/strong\u003e Flat\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\u003eInsulator Height:\u003c\/strong\u003e 50.50 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePre-Gap Size:\u003c\/strong\u003e 0.32 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eResistance:\u003c\/strong\u003e 5000 Ohm\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 087295175583\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eMercury EFI 4-Stroke outboard engines, 65 HP to 150 HP\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eMercury 33-8M0204728\u003c\/li\u003e\n\u003cli\u003eMercury 33-8M0057936\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the NGK 7558 spark plug?\u003c\/strong\u003e The NGK 7558 is a V-Power resistor spark plug built to the ZFR5F specification, designed for reliable ignition in Mercury EFI 4-Stroke outboard engines.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the NGK 7558 fit my Mercury outboard?\u003c\/strong\u003e The NGK 7558 fits most Mercury EFI 4-Stroke outboard engines rated from 65 HP to 150 HP.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the NGK 7558 the same as an NGK ZFR5F plug?\u003c\/strong\u003e Yes, NGK 7558 is built to the ZFR5F specification, so the two designations refer to the same spark plug.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the NGK 7558 replace Mercury part number 33-8M0204728?\u003c\/strong\u003e Yes, the NGK 7558 is a direct equivalent to Mercury 33-8M0204728 and also to Mercury 33-8M0057936.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat thread size does this spark plug use?\u003c\/strong\u003e The NGK 7558 has a 14 mm x 1.25 mm thread size, matching the standard thread on compatible Mercury EFI 4-Stroke cylinder heads.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the reach and hex size of the NGK 7558?\u003c\/strong\u003e This plug has a 0.749 inch reach and a 5\/8 inch hex size for use with a standard spark plug socket.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the NGK 7558 a resistor spark plug?\u003c\/strong\u003e Yes, the NGK 7558 is rated at 5000 Ohm resistance, which helps suppress electrical interference during operation.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat gap is the NGK 7558 set to out of the box?\u003c\/strong\u003e The NGK 7558 ships pre-gapped to 0.32 inches.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat materials are used in the NGK 7558 electrodes?\u003c\/strong\u003e The center electrode core is copper and the ground electrode core is nickel on the NGK 7558.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the NGK 7558 spark plug weigh?\u003c\/strong\u003e The NGK 7558 weighs 0.15 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat seat type does the NGK 7558 use?\u003c\/strong\u003e The NGK 7558 uses a flat seat design.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many spark plugs come in an order of the NGK 7558?\u003c\/strong\u003e The NGK 7558 is sold as a single spark plug, so order one per cylinder needing replacement on your Mercury EFI 4-Stroke outboard.\u003c\/p\u003e","brand":"NGK Spark Plugs","offers":[{"title":"Default Title","offer_id":49028255088859,"sku":"NGK-ZFR5F","price":4.27,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/33-8M0057936__21792.1722517140.500.750.jpg?v=1785165245","url":"https:\/\/www.goodvibesmarina.com\/products\/ngk-v-power-spark-plug-7558-zfr5f-equivalent-fits-mercury-efi-4-stroke-65-150-hp-outboards","provider":"Good Vibes Marina","version":"1.0","type":"link"}