Tiled shower spout needs replacement

[Steerpike]

The faucet in my tub need to be replaced, but the drywall is tiled over...any easy way to replace the faucet?
The problem is when I turn on the faucet the water flows just fine. But when I take a shower I need to pull up on a small toggle located on the head of the faucet. This should stop the flow of water to the faucet and channel it up to the shower head. This does not happen. It partially stops the flow of water, and so I get a half hearted flow to the shower head. Is there any other way to fix this?
Thanks for any response.

[NMDemDist2]

1. we fixed that pretty easy

you unscrew the tub faucet and replaced the valve in there, this video may help

http://www.ehow.com/video_117462_repair-tub-shower.html

[Wash. state Desk Jet]

2. You should be able to

unscrew the water outlet . Can be done with a pipe wrench or large pair of pliers ,turn it counter clock wise. Once removed,take that with you to home depot or your local hardware store and buy the exact same thing. Show it to a clerk so the the inside measurement is right. Than simply insert or screw the replacement in. The tile must be cut around the water outlet valves. Replacement part is about ten to fifteen dollars. Re look at the outlet,what you may be seeing around the outlet is caulk or tile grout to fill the gap around the cut tile. You may have to break that away. try the pipe wrench,that may do it,or chisel away around the outlet valve,the grout . Again, look it over again closely,notice the tile cut round around the outlet valve. Notice the gap that was filled in ,the space between the tile and the water outlet valve.And be careful with thar wrench, you do not want to force the valve to unscrew ,you apply pressure,but not too much. Sometimes you must go at it several time to get it to loosen, on the other hand,sometimes it is easy. It will always remove or be removed. You don't want to damage the valve or the connecting pipe between the valve and the water outlet or tub outlet.

If any of this confuses you call your local hardware store for a second opinion , you will than know what to do.

[Robb]

3. Note of caution:

There are two types of spouts, the kind that screw on and the kind that just push on. If unscrewing isn't working, look for a little screw that holds the thing on, then pull it off.

Usually when your problem is happening it's a washer that's given up. Sadly most places won't have the washer; happily, the whole valve is pretty cheap, and most places will have the valve. Bring it with you. :)