I am having an issue with my skimmer door sticking when there are waves in the pool. I have grinded down the sides so that it moves more freely, but, it still happens once in a while. I noticed that when I look into the skimmer opening from inside the pool, the collar that holds the top cover, covers almost half of my skimmer opening inside. Is this correct? The skimmer opening is rectangle shaped, and the collar is round, but it seems that would be blocking some water into the skimmer. I would assume that the whole skimmer opening should be wide open into where the skimmer basket is.... Should I cut a little section of the lower part of the collar out so that it is not blocking the skimmer opening?