The article reports on the results of an analysis of the torsind behavior long-term observations. The torsind is a species of ultralight disc torsion balance. The data analysis showed that the signal recorded contains the 24-hour periodic component presumably associated with the Sun. Moreover, unpredictable strong impacts, forcing torsind disk to rotate in one or another direction, were revealed. Presumably the reason of these effects is the Sun. This indicates the existence of an unknown radiation that bears a torque which may impact on the mechanical systems dynamics. This fact leads to the need to measure the gravitational constant G overnight and during periods of minimum of the solar activity, provided that the G measurements are carried out using a torsion balance.