Black tank valve sticking

But a lot of the times what happens is the cable inside the sheath gets rusty etc.. and then it will be harder and harder to pull the handle and open the valve then over time if you do not replace it the cable and handle will break off in your hand and then you are in a world of hurt(how would I know that):S

You have a handle attached to a rod that is fastened to a plate that slides back and forth over the opening.....The flat housing that the plate slides in and out of, drill a small hole in the middle of the flat plastic plate, screw in a grease jerk so when it starts sticking, shoot a little grease and it slides smoothly....

Lube, Spray,Blah Blah Blah been there done that with 3 of my 5er's ya just gotta buck up and replace the valve and cable before it breaks and like was said before use plumbers grease on the the new valve blades,I use Valterra like these : https://www.amazon.com/Valterra-TC372-Flexible-Cable-Valve/dp/B002N5L9R8/ref=sr_1_2?ie=UTF8&qid=1478416546&sr=8-2&keywords=valterra+waste+valve+with+cable as they are way better than stock ,it is not that big of a job just drop the underbelly and there they are and depending on you model just take out one of the walls in the basement area/Convienence center to get access to the back of the pull handles to remove them,there are also You Tube Videos on the subject that will help ya on your first one,BELIEVE ME you will like the results of putting in the new Valterra Valve/cables

Just to try it before going through all the work for a new valve, I have coated the handle shafts with Vaseline or silicone spray and worked the handle back and forth a few times. Then, added more Vaseline or silicone spray. Works for a little while longer..

Edited by Barb

I just R&R'ed my black tank valve. Remove, clean, silicone spray lube, new seals, reassemble, like new.

If the valve can still be operated, drain the tank. Replace it with a new valve well lubricated with plumbers valve grease, silicon based water proof lube. You will need to use solvent to get it off your hands when you are finished. Soap wont do it!
If the valve is siezed closed, get a honey wagon service to suck out as much as possible via the commode,
Prepare for spillage when you loosen the 7/16 head " 1/4 " valve bolts to replace/ lube the valve.
The most common trouble is the pull shaft stripping out of the bladex due to age or lack of lube.
The job is unpleasant, not worrisome when precautions are taken.

First try cleaning the tank, valve, and lubricate the handle shaft. If none of this works, replace the valve.

Replacement.

Tried all the fixes (ice in tank etc) with no results. The only thing that works is to remove the valve and lube it. If you go that far you might just as well replace the valve and seals.