{"product_id":"mercury-quicksilver-865615q10-mercruiser-serpentine-belt","title":"Mercury Quicksilver 865615Q10 Serpentine Belt – MerCruiser 5.7L \u0026 6.2L MPI MIE","description":"\u003cp\u003eQuicksilver 865615Q10 is a genuine Mercury Marine serpentine accessory drive belt measuring \u003cstrong\u003e2,195 mm\u003c\/strong\u003e in length, designed for selected MerCruiser MIE (marine inboard engine) applications with closed cooling and the \u003cstrong\u003e4-1\/4 in. idler pulley\u003c\/strong\u003e configuration. It is the current replacement for the superseded belt numbers 865615010 and 86387610.\u003c\/p\u003e\n\n\u003cp\u003eThe serpentine belt drives the alternator, seawater or coolant pump, power steering pump, and other engine accessories from the crankshaft pulley. On closed-cooled MIE configurations, belt failure risks immediate loss of coolant circulation and engine overheating — making scheduled inspection and proactive replacement an important part of engine maintenance.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eFitment note:\u003c\/strong\u003e Belt length on MerCruiser engines varies by accessory configuration, cooling system type, and idler pulley diameter. Confirm your engine model, serial number, cooling configuration, and idler pulley size (4-1\/4 in.) before ordering. The part number printed on your existing belt is the fastest fitment confirmation.\u003c\/p\u003e\n\n\u003ch2\u003eCompatible Applications\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eMerCruiser 350 MAG MPI MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 350 MAG MPI Horizon MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 5.7L MPI MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 5.7L MPI Horizon MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser MX 6.2L MPI MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser MX 6.2L MPI Horizon MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 6.2L MPI MIE\u003c\/li\u003e\n  \u003cli\u003eMerCruiser 6.2L MPI Horizon MIE\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConfiguration requirement:\u003c\/strong\u003e Closed-cooling system with 4-1\/4 in. idler pulley — confirm before ordering\u003c\/li\u003e\n  \u003cli\u003eVerify using your engine serial number — similar MerCruiser engines with different accessory or cooling configurations use a different belt length\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e 865615Q10\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMercury reference:\u003c\/strong\u003e 57-865615Q10\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Mercury \/ Quicksilver\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Serpentine accessory drive belt\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLength:\u003c\/strong\u003e 2,195 mm\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIdler pulley requirement:\u003c\/strong\u003e 4-1\/4 in. diameter idler pulley\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCooling system:\u003c\/strong\u003e Closed-cooled MIE applications\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePackaging:\u003c\/strong\u003e Genuine Quicksilver (OEM Mercury Marine)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGTIN:\u003c\/strong\u003e 745061630505\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCondition:\u003c\/strong\u003e New \/ OEM\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSupersession Chain\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCurrent number:\u003c\/strong\u003e 865615Q10 \/ 57-865615Q10\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSupersedes:\u003c\/strong\u003e 865615010\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSupersedes:\u003c\/strong\u003e 57-865615010\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSupersedes:\u003c\/strong\u003e 86387610\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSupersedes:\u003c\/strong\u003e 57-86387610\u003c\/li\u003e\n  \u003cli\u003eIf your existing belt or service records show any of the superseded numbers above, 865615Q10 is the correct current replacement\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eService Interval\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eInspect the serpentine belt at every 100-hour service interval or annually, whichever comes first\u003c\/li\u003e\n  \u003cli\u003eReplace immediately if cracking, fraying, glazing, missing ribs, or belt contamination (oil, coolant) is found\u003c\/li\u003e\n  \u003cli\u003eReplace proactively at major service intervals — a belt failure underway on a closed-cooled MIE stops coolant circulation and causes rapid overheating\u003c\/li\u003e\n  \u003cli\u003eInspect idler pulley, tensioner, and all accessory pulleys for wear, wobble, or roughness each time the belt is replaced\u003c\/li\u003e\n  \u003cli\u003eConfirm service intervals for your specific engine in the MerCruiser service manual for your model and serial range\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eBefore removing the old belt, photograph or note the belt routing, or refer to the MerCruiser service diagram for your engine\u003c\/li\u003e\n  \u003cli\u003eInspect the 4-1\/4 in. idler pulley, tensioner pulley, and all accessory pulleys for wear, wobble, bearing roughness, and alignment while the belt is off\u003c\/li\u003e\n  \u003cli\u003eRoute the new belt exactly per the MerCruiser diagram — incorrect routing causes immediate belt failure or accessory damage\u003c\/li\u003e\n  \u003cli\u003eConfirm the belt is fully seated in every pulley groove before running the engine\u003c\/li\u003e\n  \u003cli\u003eAfter startup, verify the belt tracks correctly on all pulleys with no edge riding, vibration, or noise\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical FAQ\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eQ: What’s the key fitment detail that distinguishes this belt from other MerCruiser serpentine belts?\u003c\/strong\u003e\u003cbr\u003eTwo things: the \u003cstrong\u003e2,195 mm belt length\u003c\/strong\u003e and the \u003cstrong\u003e4-1\/4 in. idler pulley\u003c\/strong\u003e requirement. MerCruiser 5.7L and 6.2L engines can use different belt lengths depending on the accessory and cooling configuration — engines without closed cooling or with a different idler pulley diameter use a different belt. Confirm both the idler pulley size and cooling system type, or simply cross-reference the part number on your existing belt.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: My existing belt shows 865615010 or 86387610 — is 865615Q10 the correct replacement?\u003c\/strong\u003e\u003cbr\u003eYes. Both 865615010 and 86387610 (and their 57- prefixed variants) are superseded by 865615Q10. This is the current Mercury OEM part for those applications.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Should I replace the idler or tensioner at the same time?\u003c\/strong\u003e\u003cbr\u003eIf either pulley shows wobble, bearing roughness, or the tensioner arm has lost spring tension, yes — replacing pulleys at the same time as the belt avoids a return service call for a related failure. See the \u003ca href=\"\/products\/mercury-mercruiser-quicksilver-tensioner-pulley-865777\"\u003eMercury MerCruiser Quicksilver Tensioner Pulley 865777\u003c\/a\u003e and the \u003ca href=\"\/products\/mercury-mercruiser-serpentine-belt-pulley-kit-8m0150824\"\u003eMercury MerCruiser Serpentine Belt \u0026amp; Pulley Kit 8M0150824\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: My belt is squealing after installation — what should I check?\u003c\/strong\u003e\u003cbr\u003eCheck belt tension first — a worn tensioner spring may not apply adequate load. Then inspect all pulleys for glazing, wobble, or misalignment. A new belt on a worn idler or misaligned pulley will squeal and wear rapidly.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What happens if the belt breaks underway on a closed-cooled MIE?\u003c\/strong\u003e\u003cbr\u003eOn a closed-cooled inboard, belt failure stops the coolant pump and causes rapid engine overheating. Shut down immediately if belt failure is suspected and do not continue running. This is why proactive belt replacement at scheduled intervals is strongly recommended on MIE applications.\u003c\/p\u003e\n\n\u003ch2\u003eRelated MerCruiser Belt \u0026amp; Pulley Products\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003ca href=\"\/products\/mercury-mercruiser-quicksilver-serpentine-belt-865615010\"\u003eMercury MerCruiser Quicksilver Serpentine Belt 865615010\u003c\/a\u003e — superseded OEM number, same application\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-quicksilver-tensioner-pulley-865777\"\u003eMercury MerCruiser Quicksilver Tensioner Pulley 865777\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-serpentine-belt-pulley-kit-8m0150824\"\u003eMercury MerCruiser Serpentine Belt \u0026amp; Pulley Kit – 8M0150824\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-seawater-pump-pulley-8m0150724\"\u003eMercury MerCruiser Seawater Pump Pulley – 8M0150724\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-power-steering-pump-pulley-8m0150723\"\u003eMercury MerCruiser Power Steering Pump Pulley – 8M0150723\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-idler-pulley-support-bushing-865193\"\u003eMercury Idler Pulley Support Bushing 865193\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/mercury-serpentine-belt-8m0218433-oem-drive-belt\"\u003eMercury Serpentine Belt 8M0218433 – OEM Drive Belt\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/sierra-serpentine-belt-marine-inboard-47-15103\"\u003eSierra Serpentine Belt – Marine Inboard | SKU 47-15103\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\u003eThe critical fitment detail for the 865615Q10 is not just the engine displacement — it’s the combination of the \u003cstrong\u003e2,195 mm belt length\u003c\/strong\u003e and the \u003cstrong\u003e4-1\/4 in. idler pulley\u003c\/strong\u003e. MerCruiser 5.7L and 6.2L MPI MIE engines with different cooling or accessory configurations can use a different belt length, so displacement alone is not enough to confirm the right part. The safest check is the part number on the existing belt — if it shows 865615010, 86387610, or either of their 57- prefixed equivalents, the 865615Q10 is the correct current replacement. Best use case is a scheduled replacement during the 100-hour or annual engine service on closed-cooled MIE applications — given that the belt drives the coolant pump on these engines, running to failure is a real overheating risk. The most common issue we see is customers ordering a belt by engine displacement without confirming the cooling configuration or idler pulley size — always verify both before ordering on a closed-cooled MIE.\u003c\/p\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":51324692365348,"sku":"865615Q10","price":203.7,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/9d93ed1a-8c19-4ea9-9cc1-1afb8584b2ca.png?v=1788152659","url":"https:\/\/marisolmarine.com\/products\/mercury-quicksilver-865615q10-mercruiser-serpentine-belt","provider":"Marisol Marine Company","version":"1.0","type":"link"}