Briggs & Stratton 31L777-3136-G5 17.5HP 500cc Engine – 1in Shaft, Electric Start

Description

Repower bogged lawn tractors with the Briggs & Stratton 31L777-3136-G5 vertical shaft engine to restore clean cutting performance across demanding properties. Commercial turf care puts severe mechanical stress on mower engines, causing oil blow-by and crankcase distortion when cutting tall grass. This 500cc 17.5HP Intek Series engine uses an overhead valve layout and an iron cylinder sleeve that maintains true bore geometry under high operating temperatures.

The 12V electric starter motor turns the crankshaft with key activation, saving operator energy during repetitive start-stop tasks on service routes. The 1-inch vertical crankshaft supports heavy electric blade clutches and transmission drive pulleys without deflection. Splash lubrication coats the cylinder bore and camshaft lobes with oil, keeping internal friction low throughout 8-hour mowing shifts.

Engine Architecture of Briggs & Stratton 31L777-3136-G5

• 500cc 17.5HP Intek OHV Powerplant: Generates high rotational torque to power commercial cutting decks through tough grass.
• 1-Inch Keyed Vertical Drive Shaft: Direct fit for commercial electric blade clutches and transmission drive pulleys.
• 12-Volt Key-Start Electric Motor: Spins the engine flywheel with key activation to eliminate manual pull effort.
• Durable Cast-Iron Cylinder Sleeve: Resists bore wear from abrasive dirt, extending engine life in severe commercial service.
• Dual-Stage Cartridge Air Cleaner: Prevents pulverized grass particles and sandy soil from entering the combustion chamber.
• Super Lo-Tone Engine Muffler: Keeps operating decibel levels within local municipal noise ordinance standards.

Commercial Advantages & Heavy-Duty Build

Built for professional lawn care contractors, this vertical-shaft engine combines dependable cutting torque with easy operation.

• A reinforced crankcase base casting absorbs vibrational harmonics from high-speed commercial cutting blades.
• Clean fuel combustion extends spark plug life and reduces fuel consumption across multi-property cutting routes.

Commercial Equipment Applications & Fit

Weighing 65 pounds dry with an industry-standard vertical mounting base and 1-inch shaft, this engine mounts straight onto commercial lawn tractors, wide-area walk-behinds, and zero-turn turf mowers without deck drilling.

Warranty Protection & Routine Upkeep

• Factory warranty terms provide 2-Years of commercial and consumer coverage on all core mechanical assemblies.

Change engine oil every 50 operating hours using 10W-30 commercial engine oil. Tap clean the pleated air filter weekly in dry summer conditions, and check the spark plug gap at 0.030 inches. Order the Briggs & Stratton 31L777-3136-G5 vertical shaft engine from Mulmotor.com for guaranteed factory-fresh units, complete manufacturer warranty coverage, and dedicated commercial equipment support.