{"product_id":"mercury-mercruiser-fuel-cooler-kit-8m0125846","title":"Mercury MerCruiser Fuel Cooler Kit – 8M0125846","description":"\u003cp\u003eThe Mercury MerCruiser 8M0125846 is the current OEM Cool Fuel pump and cooler kit for MerCruiser sterndrive and inboard engines equipped with the Gen II Cool Fuel system. It replaces the complete fuel pump and cooler assembly in one service kit, keeping fuel temperatures stable and fuel pressure consistent for the engine's EFI system — the right fix when vapor lock, fuel pressure drops, or a failed pump are causing issues on the water.\u003c\/p\u003e\n\n\u003ch2\u003eCompatible Applications\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eMerCruiser 305 CID (5.0L) V8 sterndrive \u0026amp; inboard — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 350 CID (5.7L) V8 sterndrive \u0026amp; inboard — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 377 CID (6.2L) V8 — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 454 CID (7.4L) V8 — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 502 CID (8.2L) V8 — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 496 CID engines — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eMerCruiser Black Scorpion models — Cool Fuel equipped\u003c\/li\u003e\n  \u003cli\u003eTypical serial range: 0L000000 – 0M299999 (verify against your engine serial number before ordering)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSupersedes \/ Replaces\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e861156A02\u003c\/strong\u003e — previous OEM part number\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e861156A01\u003c\/strong\u003e — earlier OEM part number\u003c\/li\u003e\n  \u003cli\u003eSierra \u003cstrong\u003e18-8861\u003c\/strong\u003e — aftermarket equivalent\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eKit Contents\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eElectric fuel pump\u003c\/li\u003e\n  \u003cli\u003eFuel cooler assembly\u003c\/li\u003e\n  \u003cli\u003eO-rings and seals\u003c\/li\u003e\n  \u003cli\u003eFuel pressure regulator filter\u003c\/li\u003e\n  \u003cli\u003eMounting hardware and fittings\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 8M0125846\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Mercury Marine \/ Quicksilver\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e OEM Cool Fuel pump \u0026amp; cooler kit (Gen II)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSystem:\u003c\/strong\u003e Cool Fuel EFI fuel delivery system\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFitment:\u003c\/strong\u003e MerCruiser sterndrive and inboard engines with Cool Fuel — confirm via engine serial number\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical FAQ\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWhat is the Cool Fuel system?\u003c\/strong\u003e Cool Fuel is MerCruiser's integrated fuel pump and cooler module that uses raw water or circulating coolant to keep fuel temperatures low in EFI applications, preventing vapor lock and protecting injectors in high-heat engine compartments.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHow do I know if my engine has a Cool Fuel system?\u003c\/strong\u003e Check your engine serial number against the MerCruiser parts diagram for your model year. Cool Fuel systems were fitted to most EFI MerCruiser V8 sterndrives and inboards from the mid-1990s through the mid-2000s.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIs this a Gen II or Gen III kit?\u003c\/strong\u003e This is a Gen II Cool Fuel kit. For Gen III systems, see the \u003ca href=\"\/products\/quicksilver-gen-iii-cool-fuel-filter-kit-35-13523\"\u003eQuicksilver Gen III Cool Fuel Filter Kit 35-13523\u003c\/a\u003e or the \u003ca href=\"\/products\/mercury-gen-iii-cool-fuel-filter-disc-35-892665-8m0204703\"\u003eMercury Gen III Cool Fuel Filter Disc 35-892665\u003c\/a\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWhat service interval applies?\u003c\/strong\u003e The Cool Fuel pump should be inspected at each seasonal service. Replace the full kit when fuel pressure is outside spec, the pump is noisy, or the cooler shows corrosion or leakage. Filter elements should be replaced annually.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRelated Products\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-fuel-module-kit-8m0047215\"\u003eMercury MerCruiser Fuel Module Kit 8M0047215\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/quicksilver-gen-iii-cool-fuel-filter-kit-35-13523\"\u003eQuicksilver Gen III Cool Fuel Filter Kit 35-13523\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-gen-iii-cool-fuel-filter-disc-35-892665-8m0204703\"\u003eMercury Gen III Cool Fuel Filter Disc 35-892665 \/ 8M0204703\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-quicksilver-fuel-pump-kit-866170a01\"\u003eMercury MerCruiser Quicksilver Fuel Pump Kit 866170A01\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/engineered-marine-products-fuel-filter-kit-35-13523-1\"\u003eEngineered Marine Products Fuel Filter Kit 35-13523-1\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch2\u003eParts Desk Insights\u003c\/h2\u003e\n\u003cp\u003eThis kit is the correct choice when you are doing a complete Cool Fuel system overhaul on a Gen II MerCruiser EFI engine — replacing the pump and cooler together rather than just the filter. The most common reason customers need this kit is a fuel pump that has failed outright or a cooler that is leaking, corroded, or restricting flow. A key thing to watch: confirm your engine is a Gen II Cool Fuel application and not Gen III before ordering, as the two systems use different components entirely. If you only need the filter service components, the \u003ca href=\"\/products\/quicksilver-gen-iii-cool-fuel-filter-kit-35-13523\"\u003eQuicksilver 35-13523 filter kit\u003c\/a\u003e may be the more appropriate starting point for Gen III engines. Always cross-reference with your engine serial number — running the wrong fuel system components can cause hard starting, fuel pressure faults, or damage to injectors.\u003c\/p\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":43563916328996,"sku":"8M0125846","price":1542.84,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/dc0409a8-7552-4fb6-8510-e36808f8b5bd.png?v=1773118430","url":"https:\/\/marisolmarine.com\/products\/mercury-mercruiser-fuel-cooler-kit-8m0125846","provider":"Marisol Marine Company","version":"1.0","type":"link"}