bathtubdrain
The lever to the lift bucket was stuck and I didn't want to force it so I took the screws out and took out the assemblage and lift bucket to inspect. I cleaned off the lift bucket and put it back in. Problem was, it wouldn't settle down to where it should go. Something was blocking it. Obviously, that's what was causing it to stick.
So two questions:
First, make sure that the clog is accessible via the overflow. Try this test... While the tub is draining slowly, pour water down the overflow through a funnel. If that drains fast, then the clog is in the horizontal arm and no clearing through the overflow will help you.
What works for me is to use a wet cloth to seal off the overflow (replace it first to make as small an opening as possible). With the tub 1/2 full of water and holding the wet cloth over the overflow vent, a plunger should then be able to clear the clog because it will force water down the drain (horizontal or vertical) rather than pushing water up the overflow pipe (or pulling air down it). Should that fail, use draino or physically pry off the grate for an auger.
The plunger should pull some amount of gunk back up into the tub while you're using it, even through the grate. If that doesn't happen and the drainage does not improve, then you may have a clogged vent. You need air behind water for it to drain quickly otherwise it's like water draining from an upside-down bottle. Cleaning the vent means going up on the roof and clearing the clog from there -- a hose at full blast will usually do this.
As for fully removing the overflow and parts... I don't know.
These photos both show Mistos parts, which of the 2 pop-ups look like yours? The top one is for commercial use, the bottom one residential. Kohler will replace the top one, if that is what you have.
Drain units also different, commercial top, residential bottom
Best Answer
These get blocked by hair and soap buildup all the time there was probably some scum on it when you removed it (now matter how clean the tub is). An old wire coat hanger can be used to scrape around and pull the remaining soap/hair out. Or the purchase of a small hand auger and slide it in and rotate to clean. I really don’t like drain cleaners in these cases but if you can just put a little down and let it sit it may dissolve the blockage once it will seal let a small amount sit in there and rinse it down. But if using drain cleaner they sometimes discolor the plumbing / tub so I never over fill the pipe if I do use cleaner.