{"product_id":"engine-44s977-0033-g1","title":"Briggs \u0026 Stratton 44S977-0033-G1 Engine — 25 HP, 1-1\/8\" Shaft","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eBriggs \u0026amp; Stratton 44S977-0033-G1 replacement engine\u003c\/strong\u003e is a \u003cstrong\u003e25 gross HP, 724cc Professional Series V-twin\u003c\/strong\u003e for select riding mower, lawn tractor and zero-turn repower applications. It features a \u003cstrong\u003evertical crankshaft measuring 1-1\/8 inches in diameter × 4-19\/64 inches long\u003c\/strong\u003e, electric start, ReadyStart and full-pressure lubrication.\u003c\/p\u003e\n\u003cp\u003eReplacement references include \u003cstrong\u003e44S877-0001-G1\u003c\/strong\u003e and \u003cstrong\u003e44Q777-3136-G5\u003c\/strong\u003e. Specific Husqvarna and Craftsman mower references are listed below to help identify the original engine and confirm the installation requirements.\u003c\/p\u003e\n\n\u003ch2\u003eEngine Specifications\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEngine number:\u003c\/strong\u003e 44S977-0033-G1\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries:\u003c\/strong\u003e Briggs \u0026amp; Stratton Professional Series\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePower:\u003c\/strong\u003e 25 gross HP\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDisplacement:\u003c\/strong\u003e 724cc\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConfiguration:\u003c\/strong\u003e V-twin, overhead valve, vertical shaft\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCrankshaft:\u003c\/strong\u003e 1-1\/8\" diameter × 4-19\/64\" length\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eKeyway:\u003c\/strong\u003e 1\/4\"\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCrankshaft end:\u003c\/strong\u003e Drilled and tapped 7\/16\"-20\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStarting:\u003c\/strong\u003e Electric start with ReadyStart\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCharging system:\u003c\/strong\u003e 16 amp\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFuel system:\u003c\/strong\u003e Gasoline with fuel pump\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLubrication:\u003c\/strong\u003e Full-pressure lubrication with oil filter\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCylinder construction:\u003c\/strong\u003e Dura-Bore cast iron sleeves\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eReplacement Engine References\u003c\/h2\u003e\n\u003cp\u003eEngine supplier cross-reference information lists \u003cstrong\u003e44S977-0033-G1\u003c\/strong\u003e as a replacement for the following complete engine numbers:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e44S877-0001-G1\u003c\/li\u003e\n  \u003cli\u003e44Q777-3136-G5\u003c\/li\u003e\n  \u003cli\u003e44Q777-0136-G1\u003c\/li\u003e\n  \u003cli\u003e44Q777-0006-G1\u003c\/li\u003e\n  \u003cli\u003e44P777-0016-G1\u003c\/li\u003e\n  \u003cli\u003e44P777-0016-E1\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eMatch the complete engine model and type, including the suffix. Installation may require transferring mower-specific components or adapting controls and wiring.\u003c\/p\u003e\n\n\u003ch2\u003eHusqvarna and Craftsman Mower Application References\u003c\/h2\u003e\n\u003cp\u003eThe following mower manuals identify original Briggs engines associated with this replacement family through engine parts catalogs. These are \u003cstrong\u003erepower candidates requiring seller confirmation\u003c\/strong\u003e of the exact engine number and installation details.\u003c\/p\u003e\n\n\u003cdiv style=\"max-width: 100%; overflow-x: auto;\"\u003e\n  \u003ctable style=\"width: 100%; border-collapse: collapse; text-align: left;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth scope=\"col\" style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003eMower reference\u003c\/th\u003e\n        \u003cth scope=\"col\" style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003eOriginal Briggs engine to match\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003eHusqvarna GTH2448T, model 917.279260\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003e445677-0476-E1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003eHusqvarna YTH2454, manual reference 287581\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003e445677-0479-E1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003eCraftsman 917.276080, 48-inch garden tractor\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003e446777-0244-E1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003eCraftsman 917.276081, 48-inch garden tractor\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px; border: 1px solid #dce3ec;\"\u003e446777-0244-E1\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003cp\u003e\u003cstrong\u003eMatch the engine currently installed.\u003c\/strong\u003e Mower names can cover different engines and production versions, and older equipment may already have been repowered. Send the seller your engine label and mower identification tag before ordering.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Details to Confirm\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShaft and PTO fit:\u003c\/strong\u003e Compare shaft diameter, length, keyway, retaining-bolt thread, clutch position and pulley alignment.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMounting and clearance:\u003c\/strong\u003e Check the engine mounting pattern and clearance around the hood, air cleaner, oil filter and exhaust.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eElectrical system:\u003c\/strong\u003e Confirm the starter, charging connection, fuel-solenoid connection and ignition shutdown wiring match the mower. Some earlier replacement instructions call for transferring a six-pin harness.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eControls:\u003c\/strong\u003e Confirm how the mower's throttle controls work with this ReadyStart engine and whether the original manual choke control is needed.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eExhaust and supplied parts:\u003c\/strong\u003e Ask which muffler, exhaust hardware and installation components are included. Original mower-specific exhaust parts may need to be reused or replaced.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\n\u003ch3\u003eIs 44S977-0033-G1 the same as 44S977-0032-G1?\u003c\/h3\u003e\n\u003cp\u003eNo. The \u003cstrong\u003e0033\u003c\/strong\u003e version has a \u003cstrong\u003e1-1\/8\" × 4-19\/64\" shaft\u003c\/strong\u003e. Briggs lists the \u003cstrong\u003e0032\u003c\/strong\u003e version with a \u003cstrong\u003e1\" × 3-5\/32\" shaft\u003c\/strong\u003e. That difference affects the PTO clutch, drive pulley and installation.\u003c\/p\u003e\n\n\u003ch3\u003eCan I select this engine by horsepower alone?\u003c\/h3\u003e\n\u003cp\u003eUse the original engine's complete model and type number first. Horsepower, mower brand and deck size alone do not establish compatibility.\u003c\/p\u003e\n\n\u003ch3\u003eIs this a complete mower conversion kit?\u003c\/h3\u003e\n\u003cp\u003eThis listing is for a replacement engine. Check the eBay seller's description for the included components and any additional parts required for your mower.\u003c\/p\u003e\n\n\u003ch2\u003eParts Help From PTO Direct USA\u003c\/h2\u003e\n\u003cdiv style=\"box-sizing: border-box; max-width: 100%; margin: 16px 0; padding: 20px; border: 1px solid #dce3ec; border-left: 4px solid #d95818; border-radius: 12px; background: #f5f8fc; color: #18283e; overflow-wrap: anywhere;\"\u003e\n  \u003ch3 style=\"margin: 0 0 10px; font-size: 21px; line-height: 1.3;\"\u003eText a Photo. Get Parts Help.\u003c\/h3\u003e\n  \u003cp style=\"margin: 0 0 14px;\"\u003eText your \u003cstrong\u003eengine model, type and code label\u003c\/strong\u003e and your mower's \u003cstrong\u003emodel and serial tag\u003c\/strong\u003e to \u003cstrong\u003e541-361-8778\u003c\/strong\u003e. Include photos of the crankshaft, PTO clutch, wiring connectors and exhaust arrangement.\u003c\/p\u003e\n  \u003ca href=\"\/pages\/parts-desk\" style=\"display: inline-block; box-sizing: border-box; max-width: 100%; padding: 12px 18px; border-radius: 8px; background: #17365b; color: #fff; font-weight: bold; line-height: 1.4; text-align: center; text-decoration: none;\"\u003eOpen the Parts Desk\u003c\/a\u003e\n\u003c\/div\u003e\n\n\u003cp\u003e\u003cstrong\u003eFitment support before and after purchase.\u003c\/strong\u003e Final engine compatibility and included installation parts should be confirmed with the selling dealer.\u003c\/p\u003e\n\n\u003cp\u003eCompare other options in our \u003ca href=\"\/collections\/engines\"\u003ereplacement mower engine collection\u003c\/a\u003e, or browse \u003ca href=\"\/collections\/pto-clutches\"\u003eelectric PTO clutch replacements\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003cp\u003e\u003cem\u003eAffiliate disclosure: This engine is sold and fulfilled by an independent seller on eBay. PTO Direct USA may earn a commission if you buy through the affiliate link. Check the seller listing for current price, availability, shipping, returns and warranty terms.\u003c\/em\u003e\u003c\/p\u003e","brand":"Briggs \u0026 Stratton","offers":[{"title":"Default Title","offer_id":53520805298543,"sku":"ENGINE-44S977-0033-G1","price":1249.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0957\/5058\/6735\/files\/briggs-44s977-0033-g1-engine.jpg?v=1790152942","url":"https:\/\/ptodirectusa.com\/products\/engine-44s977-0033-g1","provider":"PTO Direct USA","version":"1.0","type":"link"}