Hi All.......I own a 5 and a half year old (ie: out of warranty) dishwasher where the spray arm repeatedly keeps coming out from the base of the dishwasher during a wash cycle. (http://tinyurl.com/lktlyge). This means that dishes on the top tray are not cleaned properly. I have dismantled and cleaned the spray arm and the top spray bar to ensure that there were no blockages of food waste causing back pressure to blow the spray arm out. I am loathe to purchase a brand new spray arm when I cannot figure out what the real root cause might be. Would anyone have any ideas of other sections or areas that I should look at that might be causing the spray arm to blow out each time.......many thanks in advance for any help....regards Andy