A flexible high pressure fluid cleaning lance drive apparatus includes a guide rail having a longitudinal axis adapted to be positioned within a boiler water box and aligned in a fixed position with respect to a central axis of the water box. A tractor drive module is mounted on the guide rail, a helix clad high pressure fluid hose drive module is mounted on the guide rail operable to propel a flexible lance helix clad hose through the drive module along an axis parallel to the guide rail longitudinal axis, and a right angle guide rotator module is mounted on the guide rail and connected to the tractor module for positioning a rotatable high pressure nozzle carried by the helix clad hose within a guide tube attached to the rotator module.