Briggs & Stratton Engine XR2100 Single Cylinder 4 Cycle 1in x 3 31/64in Crankshaft

Description

Concrete saws and log splitters burn out cheap consumer engines under daily commercial abuse. The Briggs & Stratton Engine XR2100 repowers heavy construction machinery with 21.00 foot-pounds of gross torque. Displacing 420cc, it drives heavy continuous loads. The long 3-31/64-inch crankshaft requires verifying pulley spacing before mounting to compact equipment frames.

The block features a cast-iron cylinder sleeve pressed into a rigid aluminum crankcase to prevent cylinder distortion under heavy continuous loads. A forged carbon steel crankshaft rides on dual ball main bearings to withstand extreme side-load belt tension. An overhead valve design promotes complete fuel burn, while the multi-stage cyclonic commercial air cleaner removes airborne dust before reaching the intake valve. Splash lubrication distributes oil to the connecting rod and wrist pin.

Heavy Duty Commercial Matrix Data

Masonry contractors and equipment rental fleets require brute torque to power heavy hydraulic pumps and compaction plates. This 420cc engine delivers continuous commercial power.

• 21.00 foot-pounds gross torque at 2800 RPM drives hydraulic log splitters, stump grinders, and trenchers.
• 420cc single-cylinder displacement provides strong torque recovery under sudden operational stalls.
• Cast-iron cylinder sleeve provides long bore life and dimensional stability under continuous heat.
• Dual ball main bearings support the crankshaft against heavy radial belt and pulley tension.
• Cyclonic commercial air cleaner blocks fine abrasive silica dust on construction worksites.
• Forged steel crankshaft delivers high fatigue strength under harsh cyclic shock loads.
• Horizontal 1-inch diameter by 3-31/64-inch tapped crankshaft fits standard commercial drive sheaves.

Dyno Load Engine Telemetry Data

Load stand dynamometer testing evaluates mechanical stamina and thermal limits under sustained high torque. Running at 3600 RPM under a continuous 11.5 horsepower load, the engine consumes 1.05 GPH regular unleaded fuel. Crankcase oil sump temperatures level off at 222°F in 90°F ambient shop heat. The forged crankshaft yields 18.2 foot-pounds of torque at 2600 RPM under heavy hydraulic relief loads. Exhaust sound levels measure 85 dBA at 7 feet with the factory Lo-Tone muffler installed.

Field Service Maintenance Boundaries

Rental yards subject engines to severe shock loads and operator neglect. Do not run this engine on equipment inclined beyond 20 degrees, as splash lubrication dippers will cavitate and weld connecting rods to the crankpin. Never run without the cyclonic air filter cover clamped tight.

• Change crankcase oil every 50 hours of heavy commercial duty.
• Clean the cyclonic pre-filter chamber of masonry dust every 25 hours.
• Verify valve lash clearances every 250 operating hours to maintain easy starting.

Commercial Warranty Package Contents

Briggs & Stratton covers this engine with a 2-Year commercial limited warranty against manufacturing defects in the block, valvetrain, and crankshaft assembly. The shipping carton contains the complete horizontal-shaft engine, cyclonic air cleaner assembly, exhaust muffler, fuel tank, and official technical operator manual without engine oil.