{"product_id":"overstockdirect-ngk-laser-iridium-spark-plug-5887-6-pack-for-mercury-mercruiser-long-life-marine-ignition","title":"OVERSTOCKDIRECT NGK Laser Iridium Spark Plug 5887 — 6-Pack for Mercury\/Mercruiser, Long-Life Marine Ignition","description":"\u003cstrong\u003eHigh-performance NGK IZFR5G Laser Iridium spark plugs (part 5887) — a six-pack designed to fit many Mercury\/Mercruiser outboard and sterndrive engines requiring long-life, reliable ignition.\u003c\/strong\u003e\n\nThese NGK Laser Iridium plugs from OVERSTOCKDIRECT are engineered to meet or exceed OEM fit and function for a broad range of Mercury Mercruiser marine engines and several Optimax\/DFI\/DFI M2\/PRO XS models. Each plug uses a fine-wire iridium center electrode and a platinum ground tip, plus trivalent metal plating, to resist corrosion and make installation and removal smoother in marine environments. The technical specifications — 0.750\" reach, 14 mm thread diameter, 5\/8\" hex, .032\" pre-gap (0.8 mm), 5000 ohm resistor — match many factory requirements while delivering the durability demanded by saltwater and high-load conditions.\n\n\u003ch3\u003eWhich Mercury and Mercruiser models will these plugs fit?\u003c\/h3\u003e\n\u003cp\u003eThese NGK IZFR5G plugs are compatible with a long list of Mercury Mercruiser engines across model years. Fitment covers numerous DFI and DFI M2 powerheads and pumps, V‑135, V‑150, V‑175, 200\/225\/250 DFI\/PRO XS ranges, and many 115–225 hp Optimax units from 2003 and up where the OE specifies this part type.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eWorks with many 200 DFI, 250 DFI, V‑135\/150\/175, 200XS DFI and 115–225 hp Optimax models\u003c\/li\u003e\n  \u003cli\u003eCheck serial ranges in your service manual for exact compatibility\u003c\/li\u003e\n  \u003cli\u003eFlat seat, 14.0 mm thread diameter and 0.750\" reach match common factory specs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat materials and design features improve spark life and reliability?\u003c\/h3\u003e\n\u003cp\u003eThe center electrode uses a fine-wire iridium alloy for high melting point and minimal wear, while the ground electrode tip carries a platinum insert unless an alternate OE spec is required. Trivalent metal plating protects the threads and hex from corrosion and seizing, which is particularly valuable in marine service.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eIridium center electrode for consistent spark and extended service life\u003c\/li\u003e\n  \u003cli\u003ePlatinum ground tip increases ignitability and durability\u003c\/li\u003e\n  \u003cli\u003eTrivalent plating reduces corrosion and eases later removal\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow do these plugs affect installation and engine performance?\u003c\/h3\u003e\n\u003cp\u003eThese plugs are machined to OE-equivalent tolerances with a crush washer, 5\/8\" hex for standard tools, and a pre-gap of .032\" (0.8 mm). The integrated 5000-ohm resistor and non-removable nut electrical terminal meet ignition system requirements while limiting radio interference, and the long-projection design supports stable combustion in modern engines.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003ePre-gapped to .032\"; fine-wire center electrode supports crisp ignition\u003c\/li\u003e\n  \u003cli\u003e5\/8\" hex and crush washer included for straightforward installation\u003c\/li\u003e\n  \u003cli\u003eResistor type reduces RF interference for sensitive electronics\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow should I maintain and replace these spark plugs on my boat?\u003c\/h3\u003e\n\u003cp\u003eInspect plugs at recommended service intervals and replace them in sets to preserve balanced firing across cylinders. Look for consistent color and electrode wear; heavy deposits or irregular gaps indicate further engine or fuel-system attention is needed.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eReplace in full sets to maintain even performance across cylinders\u003c\/li\u003e\n  \u003cli\u003eTorque to manufacturer spec and reuse the crush washer per guidance\u003c\/li\u003e\n  \u003cli\u003eStore spares in a dry place and avoid cross-threading during installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\nWho is this for\n\nThese 6-pack NGK IZFR5G Laser Iridium plugs are aimed at marine owners, professional mechanics, and DIY technicians who maintain Mercury Mercruiser, Optimax, and related DFI outboard and sterndrive engines. Choose this set if you need OE-equivalent fitment, corrosion-resistant plating for marine conditions, long-life iridium performance, and a plug spec that matches many 115–250 hp engines. Always verify engine serial ranges and OEM recommendations before purchasing to ensure an exact match.\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Are these NGK IZFR5G plugs compatible with 2003 Optimax 115–225hp?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — they fit many 2003-up Optimax 115–225 hp models, but confirm your engine serial range against the listed fitment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Do these plugs require a special gap or tool for installation?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: No special tool: use a 5\/8\" socket and torque to spec; they are pre-gapped to .032\" (0.8 mm).\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"OVERSTOCKDIRECT","offers":[{"title":"Default Title","offer_id":48080343007390,"sku":"B0FL4VHLNN","price":138.48,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/overstockdirect-front-packaging-ngk-5887.jpg?v=1785780477","url":"https:\/\/northtrailauto.ca\/products\/overstockdirect-ngk-laser-iridium-spark-plug-5887-6-pack-for-mercury-mercruiser-long-life-marine-ignition","provider":"North Trail Auto","version":"1.0","type":"link"}