Device for detecting sealing performance of engine

The invention provides a device for detecting sealing performance of an engine, which includes a high-pressure gas source, a first pressure monitoring element, a second pressure monitoring element and an air duct, wherein the high-pressure gas source, a pressure-regulating element, the first pressure monitoring element, a throttling nozzle and the second pressure monitoring element are sequentially connected through the air duct; the air duct includes a high-pressure section and a low-pressure section which are mutually communicated; the first pressure monitoring element is connected onto the high-pressure section; the second pressure monitoring element is connected onto the low-pressure section; and the free end of the low-pressure section of the air duct can be operationally connected into a mounting hole of an ignition plug of the engine. Under the action of pressure, gas in the high-pressure gas source flows into a combustion chamber of the engine through the air duct, the sealing performance of the engine can be detected through observing the pressure value variation on the second pressure monitoring element, so that the inconvenience that the sealing performance of the engine can be only judged by installing the engine on a testboard to operate, the procedure is simple, the operation is convenient, and a large amount of time is saved.