You only need the spring if you intend to use the stopper.
I converted my Kohler tub to a walk in shower by having the Tubcut people modify it (worked great by the way.) Now I never need to close the tub stopper because I never want the tub to fill with water.
The tub drain was very slow and so I took the overflow thing apart and pulled out the stopper control arm and found that the spring in the stopper assembly was full of hair.
Do I need that spring in there? The tub is draining fine now, and as I said, I never want the tub stopper closed. I did not put the spring/arm back because it will just get clogged again and I don't need the stopper to close.
The tub drains to a greywater system, not to septic or sewer pipes.
What could go wrong with that spring removed?
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