Briggs & Stratton Engine Electric Start 31R5070012B5CC0001

Briggs & Stratton 31R5070012B5CC0001

The Briggs & Stratton 4155 Intek OHV is a 501cc, 15.5HP single-cylinder petrol engine positioned as a straightforward replacement for lawn tractors and ride-on mowers in the mid-range power bracket. Producing 11.4kW gross and 26.71Nm of torque, it covers the sort of domestic and light estate mowing where a machine gets regular but not punishing use. Compared to the higher-spec Intek variants, this engine keeps things simple — splash lubrication and no oil filter — making it a cost-effective option when those additional features aren't a requirement of the application.

OHV with Cast-Iron Cylinder Sleeve

Despite being the more entry-level offering in the Intek range, the 4155 still uses a cast-iron cylinder sleeve rather than a bare aluminium bore. Cast iron resists the gradual oval wear that eventually causes compression loss, keeping the engine performing consistently over multiple seasons without the need for a rebore. The OHV valve arrangement contributes to a cleaner burn and better fuel efficiency than a comparable side-valve engine.

Splash Lubrication

Oil circulation works by splash — a dipper on the connecting rod picks up oil from the sump and distributes it to the moving parts as the engine runs. It's a well-proven system used in single-cylinder engines for decades. There is no oil filter on this model, which keeps the design straightforward and maintenance requirements low. Oil capacity is approximately 1.3 litres.

Running Speed

The 4155 Intek has a top no-load RPM of 2800 — lower than the higher-output engines in this range. This is characteristic of the engine's design intent: a steady, measured power output suited to consistent mowing rather than high-speed operation, resulting in quieter, more composed running at typical working loads.

Electric Start & 9-Amp Charging System

Key start as standard, with no recoil backup on this model. The 9-amp alternator keeps battery charge topped up during use and provides capacity for electric PTO clutches or other 12V ancillaries the machine may carry.

AVS® Anti-Vibration System

The built-in AVS arrangement reduces the vibration inherent in single-cylinder engines. On a machine used for longer mowing sessions across larger plots, this lessens operator fatigue and reduces the mechanical stress that vibration imposes on the chassis and deck mountings over time.

Fuel Pump

A fuel pump is fitted as standard, drawing petrol from a remotely mounted tank — the configuration found on the vast majority of ride-on mowers and lawn tractors where the tank is positioned away from the engine.

Fitment & Compatibility

The vertical crankshaft is 25.4mm (1 inch) in diameter and 80.19mm (3.15 inches) in length. This replaces the previous model 31R5070011B5. If you need to confirm whether this engine suits your machine before ordering, get in touch with your original engine's model, type and code numbers. Our staff will be able to advise.

Specifications

Series: 4155 Intek OHV

Cylinders: Single, Cast-Iron Sleeved

Displacement: 501cc

Power Output: 15.5HP / 11.4kW Gross (26.71Nm @ 3600rpm)

Fuel Type: Petrol

Cooling: Air-Cooled

Crankshaft: Vertical, 1" (25.4mm) diameter x 3.15" (80.19mm) length

Flywheel: Heavy

Top No-Load RPM: 2800 ±100

Charging System: 9 Amp

Electric Start: Yes

Recoil Start: No

AVS Anti-Vibration: Yes

Lubrication: Splash

Oil Filter: No

Fuel Pump: Yes

Low Oil Cut-Off: No

Muffler: No

Fuel Tank: No

Oil Capacity: 1.3 litres (approx.)

Replaces: 31R5070011B5

Power and torque figures stated gross per SAE J1940 as rated by Briggs & Stratton.

Always read the owner's manual before commissioning. Damage resulting from improper installation is not covered under warranty. Shipping restrictions may apply outside of the UK — please contact us to confirm.