The Dial-ese cartridge was ahead of it’s time in the fact that it did not use a separate removable seat in the valve. There is a seat, it’s simply part of the cartridge. When the faucet is opened to allow water to pass, the center part of the cartridge comes down away from the rubber seal. Over time, the center brass portion tends to get scored by the water passing (think erosion) and then the seal will no longer do just that. A rebuild kit only renews the rubber parts, not the brass, and that’s usually what’s wrong. One can determine if this is the case by following the example in the picture. If the tapered surface is rough in any way, it’s shot. This problem is solved by installing a new cartridge. They’ll be good for 30 years or so, the rebuild kits, a couple of years….
