{"product_id":"molded-cooling-hose-32-897491-for-mercruiser-7-4l-454-mag-502-mag-thermostat-housing-to-port-exhaust-manifold-sierra-18-70943","title":"Sierra Molded Hose 18-70943, OEM 32-89749-1, Thermostat Housing to Port Exhaust Manifold, Mercruiser GM V-8 454\/502 cid","description":"\u003cp\u003eThe Sierra 18-70943 is a molded rubber hose engineered for Mercruiser MCM\/MIE GM V-8 (454 \u0026amp; 502 cid) engines, including the 74L, 454 Mag, and 502 Mag applications. This hose is designed to connect the thermostat housing to the port exhaust manifold, routing coolant through this critical section of the cooling system. Because it is molded to the specific bend and length required for this connection, it seats correctly without the kinking or stress that a straight-cut universal hose can cause at this joint.\u003c\/p\u003e\u003cp\u003eThe hose is built with a durable plastic construction in a white finish, matching the fit, form, and function of the original Mercury Marine equipment it replaces. It is manufactured to Sierra's standard for marine cooling system components, giving boat owners a direct replacement for the factory hose without modification to surrounding fittings or clamps.\u003c\/p\u003e\u003cp\u003eThis is a port-side specific hose. It is designed only for the thermostat housing to port exhaust manifold connection; the starboard-side connection uses a separate Sierra part number, so confirm which side needs replacement before ordering.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Sierra\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number:\u003c\/strong\u003e 18-70943\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Plastic\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.84 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282227722\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e 32-89749-1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Thermostat housing to port exhaust manifold\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEngine Fitment:\u003c\/strong\u003e MCM\/MIE GM V-8 (454 \u0026amp; 502 cid) engines, 74L, 454 Mag, 502 Mag\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Mercruiser cooling system hose\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eMCM\/MIE GM V-8 (454 \u0026amp; 502 cid) engines\u003c\/li\u003e\n\u003cli\u003e74L\u003c\/li\u003e\n\u003cli\u003e454 Mag\u003c\/li\u003e\n\u003cli\u003e502 Mag\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eMercury Marine 32-89749-1\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-70943 hose connect?\u003c\/strong\u003e The Sierra 18-70943 is a molded hose that runs from the thermostat housing to the port exhaust manifold on applicable Mercruiser engines.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs this hose for the port or starboard side?\u003c\/strong\u003e The 18-70943 is specifically the port-side thermostat housing to exhaust manifold hose; the starboard-side connection requires a different Sierra part number, so verify the side before ordering.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich engines is the 18-70943 hose designed for?\u003c\/strong\u003e It fits MCM\/MIE GM V-8 (454 \u0026amp; 502 cid) engines, including the 74L, 454 Mag, and 502 Mag configurations.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat OEM part number does the Sierra 18-70943 replace?\u003c\/strong\u003e This hose cross-references to Mercury Marine part number 32-89749-1.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the 18-70943 hose made from?\u003c\/strong\u003e It is a molded plastic hose finished in white, matching the original equipment construction for this cooling system connection.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-70943 hose weigh?\u003c\/strong\u003e The 18-70943 hose weighs 0.84 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-70943 a genuine OEM part or aftermarket?\u003c\/strong\u003e The 18-70943 is a Sierra-manufactured replacement hose, sold as a direct cross-reference to Mercury Marine 32-89749-1 rather than an OEM Mercury Marine part.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the Sierra 18-70943 come with clamps or fittings?\u003c\/strong\u003e The 18-70943 is supplied as the molded hose itself; no clamps or fittings are included based on available product information.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the 18-70943 hose fit a Mercruiser 454 Mag or 502 Mag engine?\u003c\/strong\u003e Yes, the 18-70943 is designed to fit Mercruiser 454 Mag and 502 Mag engines along with the MCM\/MIE GM V-8 454 and 502 cid platforms.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy does this hose need to be molded rather than a straight length?\u003c\/strong\u003e The 18-70943 is molded to the specific bend required to route coolant from the thermostat housing to the port exhaust manifold, so it seats without kinking the way a straight-cut hose could at this joint.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988363129051,"sku":"SIE-18-70943","price":45.21,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-70943_lg__02904.1558130791.500.750.jpg?v=1785189208","url":"https:\/\/www.goodvibesmarina.com\/products\/molded-cooling-hose-32-897491-for-mercruiser-7-4l-454-mag-502-mag-thermostat-housing-to-port-exhaust-manifold-sierra-18-70943","provider":"Good Vibes Marina","version":"1.0","type":"link"}