Leak testing machine with closing sequence. This application has a set of hydraulic closing units, supported on fastening points of the crankcase. These closing units operate following the bolting sequence of the crankcase. Hence, the leak test is performed in similar mechanical conditions to real work conditions. In addition, if the part is good, a micro-percussion unit marks the part with a datamatrix. Before removing the part, a Cognex camera verifies the datamatrix and finally, the leak test results and datamatrix reading are stored on a PC.