LST (Load-Sensing Timer) of Fuel Injection
The LST changes the fuel injection timing in accordance with the engine load, and obtain the characteristic of advancing. The fuel is released from the orifice on the governor sleeve via the governor shaft passage to the inlet side of the feed pump. Therefore, the pressure inside the pump housing is lowered to retard the injection timing. When the load on the engine increases (increased injection volume), the flyweights remain closed. The pressure inside the pump housing is not lowered because the orifice on the governor sleeve and the governor shaft passage are not aligned. On the contrary, when the load on the engine decreases (decreased injection volume), the flyweights open. The orifice on the governor sleeve and the governor shaft passage are aligned causing the pressure inside the pump housing to be reduced and the timing to be retarded.
