If the 6055 was made before late 2010, updating the internals would solve the click, the drive unit was tightened up and a new disk was used. Parts 6055.700 and 6055.740, you will need a pick tool like our 0220.707 to remove the old disk, likely a 6025.740 without the shock absorbing cup under it. In general the noise is only annoying and not likely to cause any harm, it is the magnet hitting the pump bottom on start up, that is what the new disk solves.