[hypoxia]

Reviving this Mach 5 thread.  If not used for a couple of weeks the pump motor would not turn.  I would use the tool I made to break it loose and it would work.  I removed the pump and disassembled it to replace the seal.  The spring on the seal was clogged with mineral deposits and would not move.  I soaked it in vinegar which cleaned it up & is like new with good spring action.  I had wondered why when I used the tool to break it loose it would flex before releasing.  The ceramic seal is mounted in rubber which caused the flex.  I will save the seal for emergency use, a new one from Headhunter is on the way.

To disassemble the Mach 5, remove the 6 long screws with a 5mm allen wrench & pull the pump end off.  Remove the small plug covering the end of the armature and use a screwdriver to hold the armature while removing the 13mm nut from the pump shaft.  Slide the pump from the shaft one piece at a time being careful to not break any of the plastic pieces.  Slide the spring loaded seal from the shaft and using a pick, pull the rubber mounted ceramic disk out.  Installation is just the opposite, do not touch the seal surface with your hands and don't pit anything on it.  No oil, etc.