I cannot crank my coleman powermate generator.

If the engine will not crank-if it has an electric start, first check the battery and connections to the starter and ground. If the battery is good and the connections are clean and tight, then I would check the ignition switch. If it clicks once when the key is turned to the start position, check for a seized crankshaft (see below) If it does not click, then it could be the starter, solenoid, or the ignition switch. If it has a manual pull start, and it will not pull, check to make sure the crankshaft can turn freely and if not, disconnect the pull starter and check it again-if it turns freely the rope start mechanism is hung up-it must be freed up before you can pull start it. If the crankshaft will not turn at all you probably have a serious problem that will require a major teardown.