Small Engines (Lawn Mowers, etc.): Small engine repair, flat gap, compression stroke

Question
How do I adjust the timing on a B&S 14.5 HP OHV, Model: 28n707, Type: 0131-01, Code: 961105ZE.

Thank you,
Jim Kight

Answer
Jim

Make sure that the magneto is set correct. The air gap should be between .010" and .012". Plug should be .030" you need some flat gap gauges that are metal between the fly wheel and the magneto. Tighten down to 2 screws be careful not to move the magneto after you set it,always check.
Timing is controled by a key way under the flywheel, if its off or the keyway is bent, there is also timing marks on the crankshaft and cam gears. these need to be lined up on top dead center. be careful as not to set them 180 degrees off or the engine will backfire. If that doesn't work check the valve clearance like the following.

Set the Cylinder you are Setting the Valves on to Top Dead Center (Both Rocker Arms will have Play in them when the Engine is at TDC) on the Compression Stroke When Setting the Valve Clearance. Now Loosen the Valve Adjuster Locks and Set the Intake Valve Clearance to .004in -.006in and the Exhaust to .007in - .009in. I have had Better Performance Out of the Mowers and Less Burnt Valves Using these Settings. Be Sure the Piston is at TDC on the Compression Stroke.