I just removed shower faucet cartrdge for the hot water to find a replacement part because the handle was stripped. When I replaced the cartridge and turned the water supply back on, the faucet would not shut off completely. I thought maybe I had done something to the cartridge; therefore, I switched the cold and hot cartridges assuming the cold would now not shut off. No change, the hot side still does not shut off all the way.

Should be able to take the handle off and close the valve with some pliers. Put the handle back on, and it should be fine.

Oh hey, I hate to be the posting police, but that was some really BAD advice there Farvaknowsbest. With advice like that I would suggest that you stay away from the plumbing page....may end up helping someone to break something and that is not why people come to this ask/help site, OK?

Deeneu, there is either sediment caught up in the hot outlet of the valve or there is some damage to the hot SEAT (the part the washer sits up against). I would flush the hot water side and then use a flashlight to see if you can see any scratches/damage to the seat of the hot side of the valve. If the seat is damaged, it can usually be removed and replaced by going to a local plumbing supply store...;)

Start there and let us know how you make out!

Mark