How do I remove the spill valve from my Karcher 620M?

In my long experience of this annoying and persistent problem with the 620M, the spill valve sticks down, not up. To remove it without damaging the cylindrical finish on the top of the spindle screw, I use a short length of thick-walled copper tube so that I can grip the screw safely with long-handled pincers and pull the spill valve assembly either out, or simply exercise it until moving freely to the "up" position under spring pressure, depending how long it was since last stripped, cleaned and lubed with silicone grease (not lithium grease as suggested elsewhere, unless you want to destroy the "O" rings).

JOAT
January 2011