Paul You have to adjust the doors in accordance with procedures in Service Bulletin ST-10-8/81. PJ Grady sells the book if you do not have it. To correctly adjust them is tedious. A critical adjustment is the contact assembly in the door (be sure it is not broken). To get it correct you will probably need to go through the procedure on each door twice. Once it is correct it rarely goes out again unless messed with. Happy Adjustments. Harold McElraft - 3354