Many engine performance problems can be linked to maintenance issues such as stale fuel, dirty air filter, fouled spark plug, and deteriorated oil.
A great way to help avoid these problems would be to perform an annual tune-up using a Briggs & Stratton engine Maintenance Kit.
Repair projects should always begin with troubleshooting - the search for the source of a problem - starting with the most obvious or simple explanation and working toward the less obvious or more complex.
Typically, starting and/or rough running conditions are found in either Fuel, Air, Compression or Spark (Ignition) Systems. Visit Troubleshooting for poor engine performance for tips on a poorly running engine.
When you're troubleshooting a small engine problem, you need to rule out the various parts or systems as possible sources of the problem. It's important to work systematically to isolate the cause rather than skipping parts or systems that you believe are in good working order.
It's a lot like looking for a set of keys: often, they're in an "obvious" place that didn't seem worth checking. The solution is not to overlook things that seem obvious. They just might hold the keys.
For successful troubleshooting:
Remember that a simple solution is not always the correct one, or may be only a partial solution. Replacing a worn spark plug may get an engine running, but the real culprit may be a carburettor that is partially blocked. In this case, the problem will probably turn up again soon.
Most four-stroke engine problems fall into one of these categories: