I have a black water shut off valve that leaks
. Every time I remove the outer sewer cap I get a palefull on my lap if I'm not careful. The main sewer line tee's off to the grey and the black water so the valve is quite deep inside the pipe with a 90 degree bend. Trying to get at it and pick anything out that may be stuck in the valve would be a timely, frustrating affair. (the trailer is quite new and I do remember a time it seemed something was stuck in the valve and now opening and closing it takes effort). Cutting the pipe and replacing, although an option would necessitate removing and replacing more pipe than I really would like to tackle.
And aside from filing the tank with water a few time and draining it along with chemical to break anything down (tried that) what options do I have?