A-B144S9770033G1-AI MODEL 44 ZTR REPOWER-25HP

One New Aftermarket Replacement Fits Briggs & Fits Stratton Professional Series 25 HP Vertical Shaft Engine (Model 44 ZTR Repower)

This Fits Briggs & Fits Stratton (B&S) Professional Series 44S977-0033-G1 is a 25 gross HP V-Twin vertical shaft engine designed as a direct repower replacement for zero-turn riders (ZTR) and lawn/garden tractors. The Model 44 ZTR Repower package replaces worn or failed engines with a modern OHV twin-cylinder unit featuring a Dura-Bore cast iron cylinder sleeve for extended service life and full-pressure lubrication with a spin-on oil filter.

Specifications

• Engine Series: Fits Briggs & Fits Stratton Professional Series V-Twin OHV
• Power: 25 Gross HP (SAE J1995)
• Displacement: 724cc
• Bore x Stroke: 3.12 in x 2.89 in
• Crankshaft: 1-1/8 in x 4-19/64 in, Tapped 7/16-20, 1/4 in Straight Keyway
• Valve Train: Overhead Valve (OHV)
• Cylinder Sleeve: Dura-Bore cast iron
• Starter: 12-Volt Electric Start
• Alternator: 16 Amp DC
• Carburetor: Float-feed type with integral fuel pump
• Air Filtration: Dual-Clean cartridge with foam pre-cleaner
• Ignition: Maintenance-free Magnetron electronic ignition
• Lubrication: Full-pressure with spin-on oil filter
• Oil Capacity: 2.0 qt (1.9 L)
• Recommended Oil: Synthetic 5W-30 or 10W-30
• Shaft Orientation: Vertical
• Mounting: Vertical

Compatible Applications

Zero-Turn Riders (ZTR) and Lawn/Garden Tractors: This engine is specifically designed as a Model 44 ZTR repower replacement for zero-turn mowers and riding tractors requiring a vertical-shaft V-Twin engine with a 1-1/8 in crankshaft. Verify crankshaft dimensions and mounting pattern before ordering.

Replaces Part Number(s):

44S977-0033-G1, 44S9770033G1, B144S9770033G1-AI

Supersedes / Interchange

Supersedes earlier Fits Briggs & Fits Stratton models including: 40H777-0124-G1, 40H777-0241-E1, 445677-0476-E1. Earlier type numbers 44S977-0014-G1 and 44S977-0015-G1 were superseded to this series.

New aftermarket replacement part - not remanufactured, not used.