{"product_id":"sierra-18-15550-v-belt-for-mercruiser-replaces-57-13458t-55-in-x-29-64-in","title":"Sierra V-Belt 18-15550, 55 Inch, Fits 7.4L 454 MAG ALPHA 1986-1988 and 454 MAG 1988-92 Engines","description":"\u003cp\u003eThe Sierra 18-15550 is a 55 inch V-belt built for marine engine service, designed to deliver OEM-quality fit, form, and function on applicable 7.4L 454 MAG engines. It is constructed with a synthetic fiber fabric cover, a special polyester cord, and a polychloroprene rubber body, giving the belt oil resistance and temperature stability for use in the demanding environment of a boat engine compartment. The polyester cord provides tensile strength to resist stretching under load, while the polychloroprene rubber compound resists cracking and glazing from heat cycling and exposure to engine fluids.\u003c\/p\u003e\u003cp\u003eThis belt is engineered as a drop-in replacement sized specifically for the 55 inch belt position on covered MerCruiser 454 MAG applications, so installers do not need to guess at length or cross-section. It fits the 7.4L 454 MAG ALPHA engine (454 cid, 8 cylinder, serial number range A631894 - B785148) and the 7.4L 454 MAG engine (454 cid, 8 cylinder, serial number range B721206 - D805068). Each belt ships as a single unit and is finished in white.\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 18-15550\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e V-Belt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Length:\u003c\/strong\u003e 55 inches (1397 mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEngine Displacement:\u003c\/strong\u003e 454 cid (7.4L)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEngine Cylinders:\u003c\/strong\u003e 8\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplicable Serial Number Range:\u003c\/strong\u003e A631894 - B785148 (454 MAG ALPHA); B721206 - D805068 (454 MAG)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.31 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Synthetic fiber fabric cover, polyester cord, polychloroprene rubber body\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Items:\u003c\/strong\u003e 1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999566744\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e7.4L 454 MAG ALPHA, 1986-1988, 454 cid, 8 cylinder, serial number range A631894 - B785148\u003c\/li\u003e\n\u003cli\u003e7.4L 454 MAG, 1988-92, 454 cid, 8 cylinder, serial number range B721206 - D805068\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat engines does the Sierra 18-15550 V-belt fit?\u003c\/strong\u003e The Sierra 18-15550 fits the 7.4L 454 MAG ALPHA engine (1986-1988, 454 cid, 8 cylinder, serial number range A631894 - B785148) and the 7.4L 454 MAG engine (1988-92, 454 cid, 8 cylinder, serial number range B721206 - D805068).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow long is the 18-15550 belt?\u003c\/strong\u003e This belt measures 55 inches (1397 mm) in length, sized for the 55 inch belt position on its covered MerCruiser 454 MAG applications.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the 18-15550 belt made of?\u003c\/strong\u003e It is built with a synthetic fiber fabric cover over a special polyester cord and a polychloroprene rubber body, giving the belt oil resistance and temperature stability.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-15550 an OEM-quality belt?\u003c\/strong\u003e Yes, the 18-15550 is manufactured to be correct in fit, form, and function for its listed 454 MAG applications, matching OEM belt performance.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow do I know if my engine's serial number matches this belt?\u003c\/strong\u003e Check your engine's serial number against the ranges A631894 - B785148 for the 7.4L 454 MAG ALPHA or B721206 - D805068 for the 7.4L 454 MAG; the 18-15550 is built for engines within these ranges.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat color is the 18-15550 V-belt?\u003c\/strong\u003e The belt is white in color.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many belts come in a package?\u003c\/strong\u003e Each package of the Sierra 18-15550 contains a single V-belt.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-15550 V-belt weigh?\u003c\/strong\u003e It weighs 0.31 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-15550 resist heat and oil exposure?\u003c\/strong\u003e Yes, the polychloroprene rubber body and polyester cord construction give this belt oil resistance and temperature stability suited to a marine engine compartment.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the 18-15550 fit any 454 MAG engine, or just certain serial numbers?\u003c\/strong\u003e It is built for 7.4L 454 MAG and 454 MAG ALPHA engines within the specific serial number ranges A631894 - B785148 and B721206 - D805068; engines outside those ranges may require a different belt length.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-15550 belt?\u003c\/strong\u003e The UPC for the Sierra 18-15550 V-belt is 030999566744.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988088893659,"sku":"SIE-18-15550","price":30.24,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/18-15550__42192.1737842686.500.750.jpg?v=1785188066","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-15550-v-belt-for-mercruiser-replaces-57-13458t-55-in-x-29-64-in","provider":"Good Vibes Marina","version":"1.0","type":"link"}