Clean engine with a Gunk type product. Remove valve cover. Loosen bolts and remove old cylinder head. One bolt is located inside valve cover area. Remove old gasket and inspect and clean that surface. Attach new head with new gasket using existing bolts. Torque to 18'#s with a cross type pattern. Attach new rocker arms and push rods.
No kinks in chain and chain is clean. Chain should have about 2cm of play up and down for tension. For multi-piece motor mounts- make sure the engine is aligned on motor mount. The torque and vibration of the motor will have a tendency to pull it off center over time. Clutch should be clean and dry of any lubricants. (temperature, humidity, altitude), and engine-to-engine variability. Due to manufacturing and capacity limitations, Briggs & Stratton may substitute an engine of higher rated power for this engine. 18.00 20.00 22.00 24.00 28.00 30.00 26.00 32.00 24.40 42.40 40.40 38.40 36.40 34.40 32.40 30.40 28.40 26.40 40R5 40R6 40N7 2000 2200 2400 2600 2800 The Briggs and Stratton 31N707 is a 501 cc (30.6 cu·in) single-cylinder air-cooled four-stroke internal combustion gasoline engine, manufactured by Briggs and Stratton. The B&S 31N707 engine has an OHV (overhead) design, cast iron sleeve and a vertical PTO shaft. This engine is equipped with float type carburetor and an electronic ignition system. duDe.