Instructional animation film showing the scheme of the operation of the steam engine. First part. MLTK. Steam distribution in a steam engine by the LENTZA valve mechanism. Longitudinal section of a steam engine with LENTZA steam distribution. Cross section of a steam engine. High pressure cylinder inlet and outlet valves. The relative position of the intake and exhaust valves C.V.D. depending on its indicator chart. Low pressure cylinder inlet and outlet valves. The second part of. MLTK. The relative position of the valves У.В.Д. and Ts.N.D. within one cycle. Inertial regulator LENTZA. Adjuster weights at an abandoned car. The increase in the number of revolutions of the main shaft at start. Displacement of the inertia ring relative to the governor shaft. Increased load. Reducing the load. Stopping steam admission. Maximum load. Eccentric of the inlet valve C.V.D. in LENTZA steam distribution. The effect of the regulator on the eccentric disc.