My barracuda g3 gets stuck on the drain after working fine for the last 4 months ago. I have the main drain turned off. I recently got a new diaphram, although it worked for a couple of weeks fine, then this started happening.

To confirm the main drain was closed, I went down there and checked, and there is no suction from the drain. If I open up the valve on the main drain, I feel the suction.

Any clues? I'd hate to have to buy something to put on the drain when it was working just fine before.