A tool for locking/unlocking a torsional vibration damper screw to/from a crank shaft of an engine includes an elongated tool body having a first end and a second end. The first end of the tool body includes a pair of engagement pins sized and spaced for engaging a pair of apertures in the torsional vibration damper. The second end of the tool body includes an aperture for receiving a fastener for engaging the second end to a mounting location on the engine. A spacer element can be utilized for mounting the second end of the tool body to the engine mounting location.