Recall 77V-186: 1976–1978 Motor Coach MC5B, 1976–1978 Motor Coach MC5C and 1 more
MOTOR COACH IND., INC. recall for service brakes, air, reported to NHTSA on Oct 25, 1977, covering about 1,182 vehicles.
The problem
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.
The fix
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.
Recall details
| Manufacturer | MOTOR COACH IND., INC. |
|---|---|
| Component | Service Brakes, Air › Supply |
| Recall started by | the manufacturer |
| NHTSA campaign number | 77V186000 |
Vehicles in this recall
| Vehicle | Model years | |
|---|---|---|
| Motor Coach MC5B | 1976, 1977, 1978 | All years |
| Motor Coach MC5C | 1976, 1977, 1978 | All years |
| Motor Coach MC8 | 1976, 1977, 1978 | All years |
Not every vehicle of these model years is included. Enter your VIN at nhtsa.gov/recalls ↗ or ask a dealer.
Frequently asked questions
What is recall 77V-186?
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.
How is recall 77V-186 fixed?
The dealer will replace all defective "o" rings with ones having extreme cold resistance properties.
Is the recall repair free?
Yes. Safety recall repairs are free at authorized dealers. Check whether your vehicle is included with its VIN at nhtsa.gov/recalls.