What is petcock?

A petcock is a small valve or tap that controls the flow of liquid or gas in a mechanical system, such as a vehicle's fuel tank or radiator. It is typically used to shut off the flow of liquid or gas, or to control the flow rate. Petcocks are commonly found on motorcycles, ATVs, and other small engines.

Petcocks are often used to allow for easy draining of liquids from a system, such as emptying a fuel tank for maintenance or storage. They can also be used to control the flow of liquid or gas to different components in a system.

In some cases, a petcock may also be referred to as a fuel shut-off valve or a fuel selector valve. It is important to properly maintain and operate a petcock to ensure the safe and efficient operation of the system it is connected to.