Exhaust Brake Butterfly Valve Assembly

1. Basic Part Information

• Part Name: Exhaust Brake Butterfly Valve / Exhaust Brake / Cut-off Brake

• Part Number: WG9416540063 (The QR code label on the body is clearly visible). The suffix "/A" typically indicates a revision or manufacturer code.

• Appearance Features:

  • Valve Body: The left side features a black cast aluminum or cast iron valve body, with a metal butterfly valve inside to control the exhaust flow.

  • Actuator: A silver cylindrical pneumatic actuator (air cylinder) is attached to the right side to drive the butterfly valve open/close.

  • Control Switch: The far right end has a blue plastic dust cap. Pressing down or pulling up controls the pneumatic circuit, thereby activating the exhaust brake function.

2. Applicable Models & Installation Position

• Applicable Models: Mainly suitable for Sinotruk HOWO light truck series, such as Hanjiang, Tongshuai, Wangpai, and other models. Some other Sinotruk models or light trucks equipped with the same engine may also be compatible.

• Installation Position: Installed in the middle or rear section of the engine exhaust pipe (typically before the muffler). It is an independent auxiliary braking device used in conjunction with the service brake (foot brake) and parking brake (hand brake).

3. Main Functions & Role

• Auxiliary Downhill Braking: On long downhill sections, the driver activates the exhaust brake switch. The pneumatic actuator then closes the exhaust pipe. This prevents smooth exhaust gas flow inside the engine, creating significant exhaust backpressure (counterforce), which forces the vehicle to decelerate and reduces the burden on the service brake system.

• Preventing Brake Overheating & Failure: Under heavy loads or during prolonged downhill driving, this effectively prevents thermal fade or even failure of the service brakes (brake pads/drums) caused by excessive temperatures, ensuring driving safety.

• Parking Assistance: In certain neutral gear conditions, the exhaust brake can also be used for brief parking assistance.