sounds very much as if the shutter cocking is gone, it a weakness with all lever wind retinas,and a simple repair, you can either get a cocking rack from Chris Sherlock and if you feel confident follow the advice on his website,but if you are not 100% sure it is not worth attempting it yourself,send it to Chris and let him work his magic, he has repaired a couple of retinas for me, including a cocking rack, and I have nothing but praise,you have a very good camera there and it is well worth getting it repaired,Richard