Aqua Lifter not working... possible fix/repair?

I have this aqua lifter and my problem was little flaps inside of the diaphrams. I opened it up and superglued them in place so they couldnt fall out of where they were supposed to be. It seemed to work. I havent had a problem since
how the heck did you manage to get that blockage cleared? What did you use to get in there to clean it?

I used a piece of string trimmer from my weed wacker. Stuck about 3 in. in the hole and twisted it back and forth in my fingers. That broke all kinds of crap off the sides and I flushed it out. I did this while the overflow was off the tank.
I took the overflow box off yesterday ( I am glad I used unions on both sides of the ball valve on the plumbing out of the overflow) and I flushed the box as clean as I could get it and I didnt see any gunk in there, other than coraline. If this new pump does not work I will have to buy another overflow box. Keeping my fingers crossed.
My display tank is overflowing... Once again it's the stupid CPR overflow box having issues with moving enough water down to the sump, and even the throttled back return pump (700 gph or so, 4 feet below the return head) and a 600 gph overflow box. The aqua lifter pump no longer has suction in 1 side and return through the other side... Both are very weak, to the point where you cant even tell which side is sucking and which side is supposed to be pushing it out... I took it apart once, cleaned out any dust, dirt, salt, etc I could find, got all the water out of the little rubber plunger things and it seemed to work a LITTLE better, so i ran the tank again, next thing I know after a few hours I can hear the return pump section of the sump is gurgling and almost empty! So I had to shut it down again for the night. Does anyone have any idea how this kind of pump is supposed to work? Or any way I could repair it? Otherwise I'm going to have to drive my self up to fosters on Monday when they are open. Here is a picture of the pump with the top removed and the inner workings, the only thing that comes out is the assembly of the red plastic, black rubber diaphragms, and magnet/metal arms... If anyone has any ideas please let me know, I don't want to make my tank suffer and wait to have filtration until monday yet...

I don't know if u found how to fix these things but it's quite simple.