POWERFUL ENGINE – Our 173cc displacement 4-stroke vertical cylinder gas engine has a max torque of 6.64ft.lbs @2500 RPM, max 3600 RPM speed, 4.4 maximum horsepower, 0.26 gal fuel tank. The engine is shipped dry so make sure you add gasoline and engine oil correctly before starting (not included). SHAFT SPECS – 7/8 in x 3.16 in Diameter, 3.16 in Length, end tapped with 3/8 in – 24 UNF; Keyway 3/16 in; Mounting pattern 8″; 3/8″-24 UNF tapped hole; 0.079 x 0.34in through-hole. Durable design runs quiet and provides smooth operation, the gas motor provides industrial-grade strength to get the job done. SAFETY & WIDELY APPLICATIONS – Built-in Force Air-Cooled and Splash Lubrication System, keeping the motor cool during extended use of time and ensuring the operator’s safety. A low oil shutoff functionality turns the engine off to prevent serious damage or failure. This engine spark plug system can take RA6HC/DCPR7E/DK7PTC spark plugs, with a clearance of: 0.027-0.0.31 in. It’s the p