My Karcher 520M, pressure switch deposited the spring on the bench when cover was opened. Can`t determine where the spring should be relocated. Appreciate any advice. I believe Simon ask this question 10 2010 !!. Machine works perfectly and only repair needed was to repair crossed screw thread on the outlet.

Peter D, July 2012

You need to seat it with the plastic catch holding it in place, so that it can not possibly short out to the electrical lugs. 2nd, you will not be able to reinstall the switch cover unless the V clip is compressed! Get a short piece of nylon twine, and run it around the Vclip (where it touches the microswitch) and run the two pieces of twine outside of the plastic switch housing. Pull on the 2 pieces of twine to compress the V clip as you install the switch top cover. After you have one of the screws in, pull on one end of the twine to remove it!
Remember to bleed the water through the karcher in order for the water pressure switch to activate and the motor to start.

William J, September 2012