A system for actuating an engine valve is disclosed. The system may include a lost motion housing having two spaced collars surrounding a rocker shaft. The lost motion housing may include an internal hydraulic circuit connecting a master piston bore with a slave piston bore. The lost motion housing may include a means for securing the lost motion housing in a fixed position relative to the rocker shaft. A master piston may be disposed in the master piston bore and a slave piston may be disposed in the slave piston bore. A rocker arm may be disposed on the rocker shaft between the spaced collars and may have a first portion adapted to contact a cam and a second portion adapted to contact the master piston. In a preferred embodiment, the system may be used to provide compression release engine braking or bleeder engine braking.