{"title":"Cummins MerCruiser Diesel 4-Stroke Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #eee;border-radius:8px;max-width:980px\"\u003e\n  \u003cp\u003eThis page is for Cummins MerCruiser Diesel 4‑Stroke engines and helps you find compatible parts and service information. Below you’ll find maintenance tips, frequently replaced components, and troubleshooting guidance. You can also browse the main \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\"\u003eMerCruiser collection\u003c\/a\u003e. Scroll down to the bottom of the page to start browsing parts for this engine. On the collection page, use the “Filter \u0026amp; Sort” controls to narrow results by horsepower, year range, and part category.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block;padding:10px 16px;background:#0b5;border-radius:6px;color:#fff;text-decoration:none\"\u003eBrowse All MerCruiser Parts\u003c\/a\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:16px;max-width:980px\"\u003e\n  \u003ch2\u003eHow to Identify Your Diesel Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the engine data plate on the valve cover\/rocker cover or timing cover; some installations also place a serial label on the transmission bell housing or near the ECM.\u003c\/li\u003e\n    \u003cli\u003eRecord the full model\/serial and any suffix letters; these indicate displacement, rating, emissions generation, and build options that determine parts compatibility.\u003c\/li\u003e\n    \u003cli\u003eNote the drive type (e.g., Bravo sterndrive or inboard) and cooling layout (raw‑water pump\/heat exchanger). These affect impellers, anodes, and exhaust components.\u003c\/li\u003e\n    \u003cli\u003eMany Cummins MerCruiser Diesel models are VM Motori–based inline engines; confirming cylinder count (I‑4 vs I‑6) helps select correct filters, belts, and pump kits.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px;max-width:980px\"\u003e\n  \u003ch2\u003eEngine Platform Overview\u003c\/h2\u003e\n  \u003ch3\u003eInline‑4 Turbocharged Diesel (VM Motori–based)\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInline‑4, common‑rail\/direct‑injection 4‑stroke diesel with ECU control and raw‑water seawater pump feeding a heat‑exchanger.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eVM Motori–derived CMD I‑4 families used with Bravo sterndrives or inboard gears (displacements commonly in the ~2.0–3.0L class).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eStrong low‑rpm torque and good fuel economy; compact packaging for mid‑size boats.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eImpeller and belt part numbers vary by pump\/alternator option; use full serial data for exact match.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eInline‑6 Turbocharged Diesel\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;margin-top:10px\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInline‑6, turbo\/aftercooled 4‑stroke diesel with electronically controlled fuel system and belt‑driven raw‑water pump.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eHigher‑output CMD I‑6 installations paired to Bravo drives or inboard transmissions for larger vessels.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eVery smooth operation with broad torque curve; suitable for heavier hulls and cruising speeds.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAir and fuel filter sizes, anodes, and impellers differ from I‑4 models; confirm by serial\/build list.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"service-kits\" style=\"padding:16px;max-width:980px\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for diesel sterndrive\/inboard installations. Always follow the official service manual for your exact model and duty cycle.\u003c\/p\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eEngine oil + filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eUse diesel‑rated oil; warm engine before draining for best results.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-oil-filters\"\u003eMerCruiser Oil Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eGear oil (sterndrive)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInspect for water intrusion and metal; replace sealing washers as needed.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/lower-unit-seal-kits\"\u003eLower Unit Seal Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003ePrimary fuel filter\/water separator\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInspect 50 hours; replace 100 hours or if contaminated\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eDrain water bowl frequently in humid\/salt environments.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-fuel-filters\"\u003eMerCruiser Fuel Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eSecondary\/engine fuel filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e100–200 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003ePrime system after replacement; check for air leaks at fittings.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-fuel-filters\"\u003eMerCruiser Fuel Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eRaw‑water pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInspect annually; replace every 1–2 seasons\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eReplace sooner if run dry or if overheat occurred.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-impellers\"\u003eMerCruiser Impellers\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAnodes (engine\/drive)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInspect monthly in salt\/brackish water; replace at ~50% wear\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eMatch anode material (zinc\/aluminum\/magnesium) to water type.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-anodes\"\u003eMerCruiser Anodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAir filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInspect 100 hours; replace as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eRestricted intake causes black smoke and power loss.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-air-filters\"\u003eMerCruiser Air Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eSerpentine\/drive belt\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eInspect 100 hours; replace ~300 hours or 3 years\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eCheck tensioner and pulleys for noise or wobble.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/belt\"\u003eBelts\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"padding:16px;max-width:980px\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service Kits – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-service-maintenance-kits\"\u003eMerCruiser Service \u0026amp; Maintenance Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-impellers\"\u003eMerCruiser Impellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-fuel-filters\"\u003eMerCruiser Fuel Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eElectrical\/Charging – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-alternators\"\u003eMerCruiser Alternators\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFiltration – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-oil-filters\"\u003eMerCruiser Oil Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-anodes\"\u003eMerCruiser Anodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003ePropulsion – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-propellers\"\u003eMerCruiser Propellers\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"padding:16px;max-width:980px\"\u003e\n  \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eOverheat at cruise or high RPM\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eSea strainer blockage, raw‑water impeller wear, loose\/broken belt, thermostat sticking, intake screen fouling\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eImpeller kit, raw‑water pump, thermostat, intake screen, hoses\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eHard starting or stalls after filter change\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003ePrime the fuel system; check for air leaks at fittings; verify battery voltage and glow plug operation (cold starts)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eFuel filters, lift pump, fuel hoses\/clamps, glow plugs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003ePoor acceleration \/ power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eClogged air or fuel filters, boost\/charge‑air hose leaks, over‑pitched or fouled propeller\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAir filter, fuel filter, turbo\/charge‑air hoses, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eExcessive black smoke\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAir intake restriction, overloaded boat, prop pitch too high, injector or turbo performance issues\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eAir filter, injectors, turbocharger components, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eGearcase noise or metal in gear oil (sterndrive)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eLow gear lube, water intrusion, worn bearings\/seals, improper shift cable adjustment\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0\"\u003eLower unit seal kit, bearings, shift cable components\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"faq\" style=\"padding:16px;max-width:980px\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable between different years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eSome filters and anodes cross between engines, but many items (impellers, belts, sensors) differ by displacement, serial range, and drive. Always confirm using the full model and serial.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should I replace the raw‑water impeller?\u003c\/summary\u003e\n    \u003cp\u003eInspect annually and replace every 1–2 seasons, or immediately after any overheat or dry‑run incident. In sandy or silty water, service more frequently.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should sterndrive gear oil be changed?\u003c\/summary\u003e\n    \u003cp\u003eTypically every 100 hours or annually. Check for water contamination and metal on the drain plug magnet; address seal issues before returning to service.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information do you need to confirm part compatibility?\u003c\/summary\u003e\n    \u003cp\u003eProvide the engine model, full serial number, drive type (e.g., Bravo), and any option codes from the data plate. Photos of the nameplate and the existing part help ensure an exact match.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px;max-width:980px;border-top:1px solid #eee\"\u003e\n  \u003cp\u003eReady to find parts fast? Browse the main MerCruiser collection by model and category, then use Filter \u0026amp; Sort to narrow by fitment.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block;padding:10px 16px;background:#0b5;border-radius:6px;color:#fff;text-decoration:none\"\u003eShop MerCruiser Parts\u003c\/a\u003e\n  \u003cp style=\"margin-top:8px;color:#555\"\u003eIf you’re unsure about your model, send us a clear photo of the engine nameplate and the part you need—we’ll help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[{"product_id":"thermostat-fits-cummins-mercruiser-qsd-2-8l-4-2l-replaces-8m0093561-879194215","title":"MerCruiser Thermostat for Cummins CMD QSD 2.8L \u0026 4.2L, 80°C (176°F) – Replaces 8M0093561","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\u003cstyle\u003e\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n  table.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\n  table.ss-table th, table.ss-table td {\n    padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n  }\n  table.ss-table th {\n    white-space:nowrap;\n    word-break:normal;\n    letter-spacing:normal;\n    font-weight:600;\n    background:#f8fafc;\n  }\n  @media (max-width:480px){\n    table.ss-table th, table.ss-table td { padding:8px 10px; font-size:14px; }\n  }\n\u003c\/style\u003e\n\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis replacement \u003cstrong\u003ethermostat\u003c\/strong\u003e is designed for MerCruiser and Cummins MerCruiser Diesel (CMD) QSD 2.8L and 4.2L marine engines. It helps regulate coolant flow so the engine can maintain its specified operating temperature.\u003c\/p\u003e\n\u003cp\u003eThe thermostat is calibrated for an opening temperature of \u003cstrong\u003e80°C (176°F)\u003c\/strong\u003e. It is supplied as one thermostat for installation in the engine cooling system.\u003c\/p\u003e\n\u003cp\u003eUse the reference numbers below to compare this replacement with the thermostat currently installed on your engine.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eApplication: MerCruiser Stern \/ Out Drive cooling systems\u003c\/li\u003e\n  \u003cli\u003eEngine families: Cummins MerCruiser Diesel CMD QSD 2.8L and 4.2L\u003c\/li\u003e\n  \u003cli\u003eOpening temperature: 80°C (176°F)\u003c\/li\u003e\n  \u003cli\u003eProduct format: Single thermostat, not a multi-component kit\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eOEM Reference Numbers\u003c\/h2\u003e\n\u003cp\u003eThe following MerCruiser reference numbers are associated with this thermostat application:\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"OEM Reference Numbers\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eReference Number\u003c\/th\u003e\n        \u003cth\u003eApplication Note\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e8M0093561\u003c\/td\u003e\n        \u003ctd\u003ePrimary reference\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e879194215\u003c\/td\u003e\n        \u003ctd\u003eReference number\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e879194233\u003c\/td\u003e\n        \u003ctd\u003eReference number\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e879194231\u003c\/td\u003e\n        \u003ctd\u003eReference number\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e896332148\u003c\/td\u003e\n        \u003ctd\u003eReference number\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine Compatibility\u003c\/h2\u003e\n\u003cp\u003eThis thermostat is listed for Cummins MerCruiser Diesel CMD QSD engine applications with the following displacements:\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine Compatibility\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eEngine Brand\u003c\/th\u003e\n        \u003cth\u003eEngine Family\u003c\/th\u003e\n        \u003cth\u003eDisplacement\u003c\/th\u003e\n        \u003cth\u003eThermostat Temperature\u003c\/th\u003e\n        \u003cth\u003eReference Numbers\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser \/ CMD\u003c\/td\u003e\n        \u003ctd\u003eQSD\u003c\/td\u003e\n        \u003ctd\u003e2.8L\u003c\/td\u003e\n        \u003ctd\u003e80°C (176°F)\u003c\/td\u003e\n        \u003ctd\u003e8M0093561, 879194215, 879194233, 879194231, 896332148\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser \/ CMD\u003c\/td\u003e\n        \u003ctd\u003eQSD\u003c\/td\u003e\n        \u003ctd\u003e4.2L\u003c\/td\u003e\n        \u003ctd\u003e80°C (176°F)\u003c\/td\u003e\n        \u003ctd\u003e8M0093561, 879194215, 879194233, 879194231, 896332148\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\u003cp\u003eConfirm the complete engine model, serial information, housing configuration, and the reference number on your existing thermostat before ordering. Displacement alone may not identify every engine variation.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n  \u003cdd\u003eThermostat\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n  \u003cdd\u003eMarine engine cooling system\u003c\/dd\u003e\n  \u003cdt\u003eEngine Family\u003c\/dt\u003e\n  \u003cdd\u003eCummins MerCruiser Diesel CMD QSD\u003c\/dd\u003e\n  \u003cdt\u003eCompatible Displacements\u003c\/dt\u003e\n  \u003cdd\u003e2.8L and 4.2L\u003c\/dd\u003e\n  \u003cdt\u003eOpening Temperature\u003c\/dt\u003e\n  \u003cdd\u003e80°C (176°F)\u003c\/dd\u003e\n  \u003cdt\u003ePackage Format\u003c\/dt\u003e\n  \u003cdd\u003eSingle thermostat\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e1 x\u003c\/span\u003e Thermostat\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eGaskets, O-rings, seals, coolant, and other installation hardware are not included unless specifically shown in the product photos or stated in the order details.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eAllow the engine to cool completely before beginning work.\u003c\/li\u003e\n  \u003cli\u003eDrain the engine coolant into a suitable, clean container according to the engine manufacturer's procedure.\u003c\/li\u003e\n  \u003cli\u003eLocate and remove the thermostat housing. Note the orientation of the old thermostat before removal.\u003c\/li\u003e\n  \u003cli\u003eRemove the old thermostat and clean the mating surfaces of the housing and engine.\u003c\/li\u003e\n  \u003cli\u003eInstall the replacement thermostat in the correct orientation. Use a new gasket or seal where required; replacement sealing parts are not included.\u003c\/li\u003e\n  \u003cli\u003eReinstall the housing and tighten the retaining bolts to the manufacturer's specification.\u003c\/li\u003e\n  \u003cli\u003eRefill the cooling system with the correct coolant and bleed air from the system as required.\u003c\/li\u003e\n  \u003cli\u003eRun the engine, check carefully for leaks, and monitor the temperature to confirm correct operation.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I know if my engine's thermostat may be failing?\u003c\/summary\u003e\n  \u003cp\u003ePossible symptoms include overheating, an engine that runs unusually cold, unstable temperature readings, poor heating performance, or coolant leakage around the thermostat housing. Diagnose the cooling system before replacing the thermostat.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat temperature does this thermostat open at?\u003c\/summary\u003e\n  \u003cp\u003eThis thermostat is specified to begin opening at 80°C (176°F).\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs a gasket included?\u003c\/summary\u003e\n  \u003cp\u003eNo. The package contains one thermostat only. A suitable new gasket or seal should be obtained separately if required for your engine.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this fit every QSD engine?\u003c\/summary\u003e\n  \u003cp\u003eThe listed application covers CMD QSD 2.8L and 4.2L engines. Confirm the complete model, serial information, housing configuration, and reference number before installation.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this an OEM component?\u003c\/summary\u003e\n  \u003cp\u003eThis listing is for a replacement thermostat associated with the MerCruiser reference numbers shown above. It is not represented as a genuine MerCruiser-branded component.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eShipping speed and cost?\u003c\/summary\u003e\n  \u003cp\u003eTypical transit is 5–15 days. Available shipping services and costs are displayed at checkout.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWarranty and returns?\u003c\/summary\u003e\n  \u003cp\u003eWarranty and return eligibility are governed by the applicable order and store policies. Contact support with your order details if you need assistance.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify the complete engine model, serial information, thermostat dimensions, housing configuration, and reference number before purchase.\u003c\/li\u003e\n  \u003cli\u003eDo not rely on engine displacement alone when confirming compatibility.\u003c\/li\u003e\n  \u003cli\u003eAlways work on a completely cool engine and follow the engine manufacturer's service procedures.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended when coolant-system service or engine-specific procedures are unfamiliar.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003ePro-Grade Standards — We supply marine replacement parts selected for dependable service in real-world marine applications.\u003c\/li\u003e\n  \u003cli\u003eGlobal Fulfillment — Shipping options and delivery estimates are provided at checkout.\u003c\/li\u003e\n  \u003cli\u003eManufacturer-Direct Value — Fair pricing with careful product and reference-number matching.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723787243835,"sku":"22TH040","price":60.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Thermostat_for_Cummins_MerCruiser_QSD_CMD_QSD_42_ES_320_QSD_28_8M0093561_-_JLM_MARINE-8291026.jpg?v=1763031750"}],"url":"https:\/\/seasierra.com\/collections\/cummins-mercruiser-diesel-4-stroke-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}