{"product_id":"low-oil-pressure-sender-sensor-switch-fits-mercruiser-4-3-5-0-5-7-replaces-87-805605a1-op22900-97767","title":"Low Oil Pressure Sender Sensor Switch – Fits MerCruiser 4.3 5.0 5.7 (Replaces 87-805605A1, OP22900, 97767)","description":"\u003cstyle\u003e\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\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  table.ss-table th {\n    white-space:nowrap;\n    word-break:normal;\n    letter-spacing:normal;\n    font-weight:600;\n    background:#f8fafc;\n  }\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 \u003cstrong\u003eLow Oil Pressure Sender Sensor Switch\u003c\/strong\u003e is designed for MerCruiser 4.3, 5.0, and 5.7 engines. It monitors oil pressure and activates the alarm system or shuts off the electric fuel pump when pressure drops to unsafe levels, protecting your engine from catastrophic damage.\u003c\/p\u003e\n\u003cp\u003eThis aftermarket replacement directly substitutes for MerCruiser 87-805605A1, Sierra OP22900, Crusader 97767, and Marine Power 457045.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eSenses low oil pressure at 6 PSI threshold\u003c\/li\u003e\n  \u003cli\u003eTerminal type: 10-32 stud; Thread size: 1\/8-27\u003c\/li\u003e\n  \u003cli\u003eShuts off electric fuel pump to prevent engine damage\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\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e87-805605A1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003eOP22900\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eCrusader\u003c\/td\u003e\n        \u003ctd\u003e97767\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMarine Power\u003c\/td\u003e\n        \u003ctd\u003e457045\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\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      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e4.3\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e5.0\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e5.7\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\u003ePressure Threshold\u003c\/dt\u003e\n  \u003cdd\u003e6 PSI\u003c\/dd\u003e\n  \u003cdt\u003eTerminal Type\u003c\/dt\u003e\n  \u003cdd\u003e10-32 stud\u003c\/dd\u003e\n  \u003cdt\u003eThread Size\u003c\/dt\u003e\n  \u003cdd\u003e1\/8-27\u003c\/dd\u003e\n  \u003cdt\u003eFunction\u003c\/dt\u003e\n  \u003cdd\u003eLow oil pressure sensing \/ electric fuel pump shutoff\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 × Low Oil Pressure Sender Sensor Switch\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the battery negative terminal and relieve fuel system pressure before beginning work.\u003c\/li\u003e\n  \u003cli\u003eLocate the existing oil pressure sender on your engine block or oil filter housing.\u003c\/li\u003e\n  \u003cli\u003eDisconnect the wiring terminal from the old sender.\u003c\/li\u003e\n  \u003cli\u003eUse an appropriately sized wrench to unthread the old sender; have a rag ready to catch residual oil.\u003c\/li\u003e\n  \u003cli\u003eApply thread sealant suitable for oil applications to the threads of the new sender.\u003c\/li\u003e\n  \u003cli\u003eHand-thread the new sender into the port, then tighten to manufacturer torque specification (typically 10–15 ft-lbs).\u003c\/li\u003e\n  \u003cli\u003eReconnect the wiring terminal to the 10-32 stud on the new sender.\u003c\/li\u003e\n  \u003cli\u003eReconnect the battery, start the engine, and verify the oil pressure warning lamp or alarm functions correctly.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eWill this fit my MerCruiser engine?\u003c\/summary\u003e\u003cp\u003eThis sender is compatible with MerCruiser 4.3, 5.0, and 5.7 models. Verify your original part number (87-805605A1) and thread size (1\/8-27) before ordering.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat does a low oil pressure sender do?\u003c\/summary\u003e\u003cp\u003eIt monitors engine oil pressure and triggers an alarm or shuts off the electric fuel pump when pressure falls below 6 PSI, preventing engine damage from lubrication failure.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I know if my sender is failing?\u003c\/summary\u003e\u003cp\u003eCommon symptoms include intermittent or constant oil pressure warning lights, false alarms at idle, or no warning when pressure actually drops. Test with a mechanical gauge to confirm.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDo I need thread sealant?\u003c\/summary\u003e\u003cp\u003eYes. Use a thread sealant rated for oil and fuel applications to prevent leaks and ensure an accurate pressure reading.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the torque specification?\u003c\/summary\u003e\u003cp\u003eTypical torque is 10–15 ft-lbs. Consult your engine service manual for exact specifications to avoid stripping the port or damaging the sender.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I test the sender before installation?\u003c\/summary\u003e\u003cp\u003eYes. Use a bench test with compressed air and a pressure gauge set to 6 PSI to verify the switch activates at the correct threshold.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\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\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\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\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify images\/specifications against 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\u003ePro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n  \u003cli\u003eFast Global Fulfillment — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003eManufacturer-Direct Value — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":51025604215099,"sku":"21SR014","price":9.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Uffa9bb4ef44440df88806114f48d8b63r.webp?v=1772931295","url":"https:\/\/seasierra.com\/products\/low-oil-pressure-sender-sensor-switch-fits-mercruiser-4-3-5-0-5-7-replaces-87-805605a1-op22900-97767","provider":"SeaSierra","version":"1.0","type":"link"}