THOMAS BUILT BUSES, INC.: Safety Recalls in 1986

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.

A BATTERY CABLE ROUTING CHANGE MAY CAUSE THE POSITIVE CABLE TO RUB AGAINST THE RIGHT FRONT SPRING REAR HANGER, POSSIBLY CAUSING A SHORT CIRCUIT IN THE CABLE AT THE POINT OF CHAFING. CONSEQUENCE OF DEFECT: A SHORT CIRCUIT AT THIS LOCATION COULD RESULT IN LOSS OF ELECTRICAL POWER TO THE VEHICLE AND COULD POSSIBLY CAUSE A FIRE.