My Pentair 4060 has the push-pull backwash handle under the bottom of the tank. I’m lately getting a slow leak from the backwash line when it’s in filter mode. I’ve tried cleaning the tank from the top and working the handle back and forth to loosen dirt but that doesn’t remedy it. I’ve seen very limited YouTubes on how possibly to fix it, replace a gasket. Looks like a bear. Is there an easy way from the top/innards of the tank? I’m not in a position where I can get under it and take things apart. I tried putting a temporary cap on the backwash line and the pressure in that line built up so high that I started getting a drip under the tank itself. Thanks.