An engine valve actuation system is provided. The engine valve actuation system
includes an intake valve that is moveable between a first position to prevent a
flow of fluid and a second position to allow a flow of fluid. A cam assembly is
configured to move the intake valve between the first position and the second position.
A fluid actuator is configured to selectively prevent the intake valve from moving
to the first position. A source of fluid is in fluid communication with the fluid
actuator. A directional control valve is configured to control a flow of fluid
between the source of fluid and the fluid actuator. A check valve is disposed between
the directional control valve and the source of fluid, only allowing fluid flow
from the fluid source to the directional control valve. A bleed orifice may be
disposed between the directional control valve and the source of fluid, in parallel
with the check valve.
