{"product_id":"hinge-pin-tool-fits-mercruiser-alpha-bravo-replaces-91-78310-18-9861","title":"Hinge Pin Tool – Fits MerCruiser Alpha \u0026 Bravo (Replaces 91-78310, 18-9861)","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\u003cstyle\u003e\n  \/* Outer container allows horizontal scrolling (with iOS momentum) *\/\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n\n  \/* Base table styles *\/\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\n  \/* Key: prevent wrapping, word breaks, and vertical text in headers *\/\n  table.ss-table th {\n    white-space:nowrap;       \/* Do not wrap *\/\n    word-break:normal;        \/* Don’t break words *\/\n    letter-spacing:normal;    \/* Prevent theme styles from stretching letters *\/\n    font-weight:600;\n    background:#f8fafc;\n  }\n\n  \/* Small screen optimization *\/\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 specialty \u003cstrong\u003eHinge Pin Tool\u003c\/strong\u003e is designed for removing and installing the hinge pins on both port and starboard sides of MerCruiser sterndrive bell housings. It is compatible with a wide range of models, including Alpha One (Gen I \u0026amp; II), Bravo (I, II, \u0026amp; III), MC-1, R, and MR sterndrives, ensuring broad application for many boat repair and maintenance tasks.\u003c\/p\u003e\n\u003cp\u003eIt serves as a direct replacement for multiple OEM and aftermarket part numbers, including Mercury 91-78310, Sierra 18-9861, GLM 90200, and Mallory 9-79805.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eConstructed from high-strength hardened steel for durability.\u003c\/li\u003e\n\u003cli\u003eFeatures a 12-point Allen style head for a secure fit on the hinge pin bolt.\u003c\/li\u003e\n\u003cli\u003eEngineered for manual use with a direct drive connection.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number Matrix\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003ePart Number\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003e91-78310\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-9861\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e90200\u003c\/td\u003e\n      \u003c\/tr\u003e\n       \u003ctr\u003e\n        \u003ctd\u003eMallory\u003c\/td\u003e\n        \u003ctd\u003e9-79805\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eConfirm your engine model\/year in the table below.\u003c\/p\u003e\n\u003cp\u003eThis tool fits a comprehensive range of Mercury MerCruiser sterndrive models. Please verify your specific drive model and serial number range where applicable.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eModel\u003c\/th\u003e\n        \u003cth\u003eRated HP\u003c\/th\u003e\n        \u003cth\u003eStroke\u003c\/th\u003e\n        \u003cth\u003eYears\u003c\/th\u003e\n        \u003cth\u003eOEM Part No.\u003c\/th\u003e\n        \u003cth\u003eNotes\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\u003eAlpha One Gen I\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e1998 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003eTrim sender covers hinge pin\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eAlpha One Gen II\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e1998 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003eTrim sender covers hinge pin\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo I\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003eMultiple serial ranges supported\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo II\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003eMultiple serial ranges supported\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo III\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003eMultiple serial ranges supported\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo X One\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e0M100001 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo X Two\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e0M100001 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo X Three\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e0M100001 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo X Four S\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo XR One\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e0L914990 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo XR Sport\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo XR Sportmaster\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003e0M052945 \u0026amp; Up\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo XR Three\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eBravo XZ One\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eHigh Performance Transom\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eIntegrated Transom\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003eMultiple serial ranges supported\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eMC-1\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eR\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eMR\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eQuicksilver Alpha One\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eAll\u003c\/td\u003e\n\u003ctd\u003e91-78310\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eSpecialty Marine Service Tool\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eManual\u003c\/dd\u003e\n  \u003cdt\u003eMaterial\u003c\/dt\u003e\n\u003cdd\u003eHardened Steel\u003c\/dd\u003e\n  \u003cdt\u003eTool Type\u003c\/dt\u003e\n\u003cdd\u003e12-Point Allen Style\u003c\/dd\u003e\n  \u003cdt\u003ePurpose\u003c\/dt\u003e\n\u003cdd\u003eHinge Pin Removal\/Installation\u003c\/dd\u003e\n  \u003cdt\u003eConnection\u003c\/dt\u003e\n\u003cdd\u003eDirect Drive\u003c\/dd\u003e\n  \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eUsed to remove and install hinge pins on port and starboard sides of sterndrive bell housings\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 x Hinge Pin Tool (91-78310\/18-9861\/90200\/9-79805)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cp\u003eThis tool is used on the hinge pin bolt to separate the gimbal housing from the gimbal ring. On most MerCruiser models, the trim and tilt sender covers the hinge pin access point and must be removed before you can use the tool. Once access is clear, the tool is used to properly remove and reinstall the pivot bolts on both the port and starboard sides of the bell housing.\u003c\/p\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is this tool specifically used for?\u003c\/summary\u003e\n  \u003cp\u003eThis tool is designed to remove and install the hinge pins that connect the sterndrive bell housing to the gimbal ring on MerCruiser drives. It features a 12-point head that correctly fits the hinge pin bolts.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDo I need to remove other parts to access the hinge pins?\u003c\/summary\u003e\n  \u003cp\u003eYes, in most applications, the trim and tilt sender unit is mounted over the hinge pin. You will need to remove the sender to gain access to the pin before using this tool.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I know if this tool fits my specific MerCruiser model?\u003c\/summary\u003e\n  \u003cp\u003eThis tool is compatible with Alpha One (Gen I \u0026amp; II), Bravo (I, II, III, and various X\/XR models), MC-1, R, and MR sterndrives. Please consult the compatibility table on this page to confirm your specific model and year range.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are the signs that my hinge pins need service or replacement?\u003c\/summary\u003e\n  \u003cp\u003eSigns of failing hinge pins include excessive play or looseness in the sterndrive when steering, unusual noises during turning, or visible corrosion and wear on the pins themselves during inspection. A loose feeling at the helm can often be traced back to worn hinge pins.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow does this aftermarket tool compare to the OEM version?\u003c\/summary\u003e\n  \u003cp\u003eThis tool is manufactured from high-strength hardened steel to meet or exceed OEM specifications for strength and durability. It provides the same functionality and fit as the original manufacturer's tool at a more accessible price point.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\n  \u003cp\u003eThis listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\n  \u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\n  \u003cp\u003eCovered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused \u0026amp; in original condition). See our policy page or reach out for instructions.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended for safety and performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50717896704315,"sku":"Y5-MNNG-USXU","price":9.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Y5-MNNG-USXU.png?v=1762937717","url":"https:\/\/seasierra.com\/products\/hinge-pin-tool-fits-mercruiser-alpha-bravo-replaces-91-78310-18-9861","provider":"SeaSierra","version":"1.0","type":"link"}