Rodger i am having the same exact issued that the OP is having with his 9015, When i dissassembled it i noticed that i had the 'bell shaped housing' as well, I did not have the part that you noted in your picture. Im assuming the same thing is wrong with my skimmer. No matter what i do i just cant get this thing to skim. Would you be able to send me the peices that you sent the op to Fix this issue? this is just very frustrating.
Ps i have assembled this thing everyway possible following all the skimmer threads in this forum and nothing works, Please help!