A liquid delivery system includes a source of hydraulic fluid and a hydraulic cylinder fluidically coupled to the source of hydraulic fluid and having a hydraulic piston movable between first and second limit positions. The liquid delivery system includes a rod connected to the piston and extending out of the hydraulic cylinder and a sensor device located outside the hydraulic cylinder and configured to sense a position of the rod and to generate a signal indicating the sensed position. The liquid delivery system includes a liquid cylinder comprising a liquid piston, operably driven by the rod, to pump a liquid along a flow path to a fluid applicator.