Phenomenon of load losses at the engine start-up stage

Summary. In the paper are presented the results of exhaust gas scavenging testing for the start-up speed. The speed of SB-3.1 engine was determined by means of external driving device composed of a three-phase motor, gearbox, unidirectional clutch and control desk. The obtained findings allowed for an evaluation of the character of changes in the course of exhaust gas scavenging curve from a basic zero speed to the rotational speed of engine crankcase at which the start-up takes place. Exhaust gas scavenging measurements were made in different measuring series in order to determine the effect of oil film development on cylinder bearing surface on the phenomenon of exhaust gas scavenging into crankcase casing.