running

I have the older mansfield toilet with the white flush valve, and it is constantly running, saturday it was so bad you could hear it a few rooms away. I replaced the red gasket seal but I don't think I needed to it was still flat and not warped or cupped. What made me think it was the red seal...

I woke up to the sound of the toilet water running, in inspecting it it looked like the flush valve was letting water through. After adjusting it the water is still filling up and overflowing, even when I manually lift the flush valve all the way to the top the water keeps pouring. Trying to...