Help - Sticking Gate valve

[lebolewis]

This is a fairly new Thetford black water tank gate valve....I installed it 4 years ago....the old original one was leaking. The new one is now sticking when I try to open it to do a dump. It started with a "slight" stick and now I can barely get it open. I am fearful of pulling the rod and handle out of the gate slide....that's my worse case fear. It is a pain in the asset to replace the valve and very, very involved. I have tried putting 1/2 cup of dish soap in the tank after I empty it to see if that will lubricate the seals.....but that hasn't helped. I'm now thinking something like Auto Transmission Fluid!! Has anyone tried that? All recommendations will be appreciated. I definitely DO NOT want to replace that valve!! Bill

[Crusty]

I put some vegetable cooking oil (a cup or two) into the black tank to keep the valve lubricated after every dump. If you're putting enough in, the valve will get easier to open (and especially) close.

[Bluto]

Also, Thetford sells a lube that you put in the tank.