Leak down is the percentage of compression that is lost by the engine, and every engine has some A cylinder leak down test kit will typically consist of the primary guage set which includes a pair of gauges, a regulator to set the pressure of incoming shop air, and a hose to connect to the spark plug adapter. Like a compression test, a leak down test is accomplished by replacing a spark plug with the tester hose.
Amazon.com: Cylinder Leak Down Tester,Compression Test kit - Engine
The complete kit includes pressure regulated manifold with dual gauges, 24 in
Note that a leak down tester will differ from an engine compression tester
