Sounds like whatever the screw is biting into is stripped and I am no plumber by any means but that loose screw may be your whole problem???? I honestly have no idea what your refering to so I can't say for sure. However, you might try putting a flat blade screw driver behind what ever this screw is holding on and ever so slightly pull on it with a little force (I.E. prying a bit) while turning the screw and see if it starts to back itself out. Don't over do it, just use enough force to apply some pressure to the screw head to help it back itself out.

That or a pair of needle nosed pliers.

Or take the other side and it's seat out, go to the plumbing supply or hardware and get two new stems, two new seats and the right sized drill bit to drill out that stubborn screw or its head.

Thanks a lot for answering. The problem is, this is a shower on a tiled wall. There is no way to get behind the shower valve without ripping out the tiles. And this darn screw is set an inch inside the handle base in a little tiny hole just larger than the screw, so that I don't see how to get pliers into it. And finally, there is only one handle, not two- and no stems. The handle attaches directly ( with this little screw) to the ceramic disc valve, which attaches to the water pipe. A different thingee handles the hot/cold mix. Won't drilling out the screw ruin the shower? Any more ideas? This link is to a pdf file of the valve- Mine is all exterior, it doesn't have the concealing plate.

Here is a link that might be useful: shower specs

Hi,
You need to pull the handle out while turning the screw. If you have withdrawn the screw 1/8, there should be that much room to pull or pry the handle. This effort should allow the threads to re-engage themselves in the valve stem. If this fails, I'm afraid you'll have to cut off the handle so the screw can be withdrawn by other means. (pliers, drilling out, heat)
In all likelihood, you should be able to find a similar if not identical replacement for the handle. The inside threads of the valve stem may need to be chased with a tap before putting in the new screw.
Casey

Hello, I have had that problem with Moen Faucets with plastic knobs. An Example, if the stem shaft is square the handle will have a shaft with a square hole to turn the knob. If the plastic shaft breaks the valve wont work correctly and when you try to remove the screw, the stem shaft will turn inside the handle. So cut the plastic handle off the hold the stem and remove the screw.
Good Luck Woodbutcher

I'm with sombreuil_mongrel, pull out the handle while you're removing the screw. If that doesn't work it's time to cut the handle off and replace it.

Thank you everyone. The update is that nothing seemed to work until I drilled the head off the screw (took me 5 hours). As soon as that happened, the screw fell off easily, and with it, the handle. I put in a new ceramic disc assembly and- no more leaks! I found this to be a very difficult project, and never did figure out why the screw would turn but not come out. I appreciate the help.

@meloni, thanks a lot! yeah I just signed up here to thank you lol. I'm having the exact problem as yours and been looking around for solution. That thread is a really good idea. I'll give it a try soon.

I'm having the same problem but mine are in my skateboard. Every one of them are turning freely but are not getting out. I need to replace the bearings but the darn screws won't loosen.

Tim-

Do they turn in both directions? If so, it probably means they are stripped. I may be able to give you some advice if I can have more details about the heads on these screws and how many per wheel. In particular, a picture would help.

if they are turning freely then they aren't holding anything. Can you pry up on the part the screws are supposedly holding and put some tension in the screw? While there is tension in screw try backing it out with a screwdriver. It should catch something and start to come out.

If the skateboard screws have a nut on the other side, then you need to stop the nut from spinning to get the screw out.

I am having a similar problem. Wood phillips head screw is seated deep in a hole, securing a wood bar and rest of window seat to the wall (we are demolishing the window seat). Screw turns, isn't stripped, but nothing we do pulls it out. No room for pliers or a wire. Not sure what else to do besides go buy a sawsall and cut off the wood on either side.

The hole is maybe stripped, or the head could have snapped off from the shaft if it was over driven. I rather doubt you need a Sawzall, though. But unless you post a picture of the whole thing and say how deep the screwhead is embedded, we could speculate on possible approaches all day.