OFFICIAL NHTSA RECALL
77V186000
Service Brakes, Air:supply
Reported Oct 25, 1977 · MOTOR COACH IND., INC.
Summary
THE INVOLVED VEHICLES DO NOT CONFORM TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "AIR BRAKE SYSTEMS". THE TWO "O" RINGS THAT ARE SUPPLIED ALONG WITH THE NEW SHUTTLE VALVES ARE OF A BUNA "V" QUALITY. THESE RINGS ARE FULLY FUNCTIONAL IN NORMAL CLIMATE CONDITIONS, HOWEVER, IN EXTREMELY COLD ENVIRONMENTS, SLIGHT LEAKS MAY DEVELOP. THIS VALVE ACTS AS A SEAL BETWEEN THE CYLINDER HEADS OF THE SHUTTLE VALVE AND THE PISTON. IN TIME THIS SEAL MAY EXPAND OR "PUCKER UP", MAKING IT POSSIBLE FOR THE SHUTTLE TO BECOME TRAPPED IN AN EMERGENCY BRAKING SITUATION.
Consequence
Not supplied in the source record.
Remedy
THE DEALER WILL REPLACE ALL DEFECTIVE "O" RINGS WITH ONES HAVING EXTREME COLD RESISTANCE PROPERTIES.
Notes
VEHICLE DESCRIPTION: MOTOR HOMES EQUIPPED WITH NEW SHUTTLE VALVES.SYSTEM: SERVICE BRAKES; AIR CONTROL VALVE.CONSEQUENCES OF DEFECT: IN THIS EVENT, THE BRAKES ONCE "ON" WILL NOT RELEASEAND LOSS OF VEHICLE CONTROL AND AN ACCIDENT COULD RESULT.NOTE: DRIVER SHOULD BE ALERTED TO THIS CONDITION BY A FLASHING LIGHT, BUZZER,AND A LOW READING ON THE AIR GAUGE.
This campaign page uses the representative official campaign record. Applicability-specific source variants appear on the linked vehicle pages. Recall counts refer to campaigns, not affected vehicles.
Vehicle entries in this campaign
This is model-level recall history. It does not confirm whether a particular VIN is affected or has received the repair. Check with NHTSA ↗