{"product_id":"alternator-belt-121850-42280-for-yanmar-4lha-4lh-marine-diesel-engine","title":"Alternator Belt 121850-42280 for Yanmar 4LHA 4LH Marine Diesel Engine","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eAlternator belt 121850-42280E for Yanmar 4LH and 4LHA marine diesel engines, the belt that drives the alternator off the crank pulley. It replaces 121850-42280E and 121850-42280, and it ships in a 200 x 250 x 50 mm pack at 170 g.\u003c\/p\u003e\n\n\u003cp\u003eIt fits the whole 4LHA family, from the DTE through to the STZP, and the 4LH family, from the DTE through to the WSTZY. These are the four cylinder Yanmars found in sail drives, workboats and small fishing vessels, where a belt that lets go means no charging and no water pump.\u003c\/p\u003e\n\n\u003cp\u003eAlternator belts on a marine diesel fail slowly and then all at once. A glazed belt slips, the alternator stops charging, and the batteries go flat over a long day. A frayed belt can take the water pump belt with it. Keeping a spare on board is cheaper than a tow.\u003c\/p\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eSpecification\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eCondition\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eNew \/ New with tags\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eType\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eMarine engine alternator belt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eFits\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eYanmar 4LH and 4LHA marine diesel engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eReplaces\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e121850-42280E, 121850-42280\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eContents\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eAlternator belt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eNet Weight\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e170 g including packaging\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003ePack Size\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e200 mm x 250 mm x 50 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eWarranty\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e3 year\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eOEM Cross Reference\u003c\/h2\u003e\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eComponent\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eOEM Part Numbers\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eAlternator belt\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e121850-42280E\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eAlternator belt, alternate\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e121850-42280\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eCompatible Engines\u003c\/h2\u003e\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eEngine Series\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eModels\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4LHA\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e4LHA-DTE, 4LHA-DTP, 4LHA-DTZE, 4LHA-DTZP\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4LHA\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e4LHA-HTE, 4LHA-HTP, 4LHA-HTZE, 4LHA-HTZP\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4LHA\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e4LHA-STE, 4LHA-STP, 4LHA-STZE, 4LHA-STZP\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4LH\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e4LH-DTE, 4LH-DTZ, 4LH-HT, 4LH-HTE, 4LH-HTZ, 4LH-HTZAY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4LH\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e4LH-ST, 4LH-STE, 4LH-STZ, 4LH-STZAY, 4LH-TE\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4LH\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e4LH-UT, 4LH-UTZ, 4LH-UTZAY, 4LH-WST, 4LH-WSTZY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat's Included\u003c\/h2\u003e\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eComponent\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eDetail\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eQty\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eAlternator belt\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eAs pictured\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eWater pump belt\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eNot included, check it at the same time\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eTensioner and pulleys\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eNot included\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eSigns The Belt Needs Replacing\u003c\/h2\u003e\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eWhat You See\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eWhat It Means\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eWhat To Do\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eAlternator warning light on at idle\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eBelt slipping\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eCheck the tension, fit a new belt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eBatteries going flat over a day\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eAlternator not turning fast enough\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eFit the new belt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eSqueal when the engine starts cold\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eGlazed or loose belt\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eFit the new belt and set the tension\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eCracks across the belt ribs\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eRubber aged out\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eFit the new belt now\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eFrayed edges\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eBelt running out of line\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eCheck the pulley alignment, fit a new belt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eBlack dust around the front cover\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eBelt wearing on a pulley\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eInspect the pulleys and fit a new belt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eFitting Notes\u003c\/h2\u003e\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eStep\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eAction\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e1\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eCheck the engine model against the 4LH and 4LHA fitment tables\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e2\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eIsolate the batteries and disconnect the alternator wiring if needed\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e3\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eLoosen the alternator mounting bolt and the adjuster\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e4\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003ePush the alternator in and slip the old belt off\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e5\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eCheck the pulleys for rust, wear and alignment\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e6\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eFit the new belt over the pulleys, not over the fan\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e7\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eSet the tension and tighten the adjuster, then the mounting bolt\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003e8\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eRun the engine and check the belt runs true and the alternator charges\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eCondition \u0026amp; Warranty\u003c\/h2\u003e\n\u003ctable style=\"width:100%;border-collapse:collapse\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eItem\u003c\/th\u003e\n\u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:6px\"\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eCondition\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eNew \/ New with tags\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003eWarranty\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003e3 year\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:6px\"\u003ePackaging\u003c\/td\u003e\n\u003ctd style=\"padding:6px\"\u003eSealed retail packaging\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eBefore You Buy\u003c\/h2\u003e\n\u003cul style=\"list-style:none\"\u003e\n\u003cli\u003eFits Yanmar 4LHA-DTE through to 4LHA-STZP\u003c\/li\u003e\n\u003cli\u003eFits Yanmar 4LH-DTE through to 4LH-WSTZY\u003c\/li\u003e\n\u003cli\u003eReplaces 121850-42280E and 121850-42280\u003c\/li\u003e\n\u003cli\u003eBelt only, no tensioner or pulleys in the pack\u003c\/li\u003e\n\u003cli\u003eCheck the water pump belt at the same time\u003c\/li\u003e\n\u003cli\u003eKeep a spare on board, a failed belt means no charging\u003c\/li\u003e\n\u003cli\u003e30-Day Easy Returns\u003c\/li\u003e\n\u003cli\u003eShips from our warehouse with tracking\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"XRmarine","offers":[{"title":"Default Title","offer_id":68109228867627,"sku":"23BL247","price":18.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0689\/0415\/7227\/files\/10_9e0cfa9d-5fbb-4c22-892c-a0f9f637ccb5.jpg?v=1793673874","url":"https:\/\/xrmarineparts.com\/products\/alternator-belt-121850-42280-for-yanmar-4lha-4lh-marine-diesel-engine","provider":"XRmarine","version":"1.0","type":"link"}