Hey Grong, what is your siphoning technique? In short how do you get the water out without turning the machine upside-down?
I use a 3-foot length of flexible plastic tubing from the hardware story. I coil it up, keeping the ends at the same height, and run tap water through one end of the tube and out the other until there is a full column of water.
Then I keep one finger tight on the drain of the hose, over the sink. The other end I lower into the bottom of the boiler of the espresso machine. At this point, most or all of the column of water should be intact inside the tube. If so, the drain end of the hose is lowered below the tank level, into the sink, in my case. With your finger removed from the drain end, the siphon effect takes place, and the tank will empty directly.
Let me know if I need to clarify this description.