Work stoppages at Honda’s North American assembly plants, which employ thousands of workers, will begin sooner than expected. Marysville, Ohio-based Honda of America Manufacturing Inc. said late Tuesday that it will begin adjusting production schedules at all of its domestic automobile plants Wednesday in an effort to conserve parts and avoid extended shutdowns. The company and other automakers are at the mercy of parts vendors that have been battered by the earthquake, tsunami and nuclear power plant troubles in Japan. Rolling power outages and damaged rail lines and highways have dramatically slowed or stopped car parts production and shipping in the Asian nation since the quake struck March 11. The daily stoppages could range from a few hours per shift to a full day.