Good Morning, Last time we went out, after hooking up to the sewer line at the campground, my black tank lever was super hard to open. Not sure why or what preventative maintenance can be done to en...
I tried the usual and was unable to free the valves. I ended up replacing them with new valtera parts. Mine were in a very difficult area to get to so I bought new valves to be safe. If yours are fairly easy to get out and you don't have luck with the other suggestions, you can pull em, clean em and lubricate with vasaline. You can also replace just the rubber seals. The valves are different sizes.