A rotary ball shower faucet uses a valve with a ball as the main water flow control mechanism, instead of a cartridge with ceramic disks. An older type of faucet, it is still possible to fix with replacement parts available through a plumbing supply store or your hardware store.
Repairing this type of faucet is a little more involved than fixing a cartridge shower faucet, but it still only takes about an hour to complete the job.
Turn off the home’s water.
Remove the cap on the handle of the rotary ball shower faucet. Take out the screw under the cap with either an Allen wrench or regular screwdriver, depending on the type of screw head. Pull the handle off the shower faucet with your hands.
Turn the round cover, called the dome cap, which is located under the handle counterclockwise using large pliers if necessary. Only apply a moderate force to unscrew this part to avoid damaging the faucet.
Take out the round cover under the dome and the washer on top of the ball lever. Pull out the ball lever and remove the two rubber gaskets (called seat springs) inside the faucet body. Use the tip of the screwdriver or Allen wrench to remove these parts.
Replace the two seat springs inside of the rotary faucet body. Place a new rotary ball valve into the faucet so the holes are positioned on the top.
Put the washer and cover back on and replace and tighten the dome cap. Set the handle back on the shower faucet lever and tighten the handle screw securely.