What causes a troy bilt mower to run then sputter then die?

Answer 1

The best way to determine why the engine sputters and dies is to inspect the spark plug after the engine dies. There are two most likely reasons. In the first example, the engine will most likely just sputter and die. In the second, the engine will generally blow black smoke when it sputters.

(1) The spark plug greyish is dry: It is likely that the fuel filter is too clogged to allow flow of enough fuel to keep the engine running. If the fuel filter is not clogged, then the carburetor needs adjustment.

(2) The spark plug is coated with black carbon or is wet (or both): The engine is running rich and is flooding. Likely causes are a dirty/faulty spark plug; a dirty/clogged air filter; or the carburetor is set too rich.