NHTSA campaign 86V079000

THOMAS BUILT BUSES, INC. recall 86V079000

TWO THROTTLE RETURN SPRING DEFECTS ARE INVOLVED IN THIS RECALL. (1) BUSES EQUIPPED WITH CATERPILLAR ENGINES MAY HAVE A THROTTLE RETURN SPRING THAT BREAKS AND PREVENTS THE THROTTLE FROM RETURNING TO IDLE POSITION WHEN THE DRIVER'S FOOT IS REMOVED FROM THE ACCELERATOR CONTROL; (2) BUSES EQUIPPED WITH CUMMINS VT-225 ENGINES MAY HAVE THE THROTTLE RETURN SPRING CONNECTED TO THE THROTTLE SLAVE CYLINDER INSTEAD OF THE FUEL INJECTION PUMP LEVER. IF FAILURE OCCURS IN THE ACCELERATION CONTROL SYSTEM, THE ENGINE MAY ACCELERATE TO ITS MAXIMUM GOVERNED RPM. CONSEQUENCE OF DEFECT: IN EITHER CASE, THROTTLE CONTROL WILL BE LOST WHICH MAY RESULT IN AN ACCIDENT.