Hard turning water valve

Klawman

Just recently I noticed that one of two valve controls for an upstairs bath is becoming very hard to turn. (The Cold control) Is this unusual or not and is there a problem I should look for? Access to the fixture appears to be very limited as the tub is set in a plywood box enclosed by tiles.

I wonder if this is a result of 20 years of house settlement possibly capped off by the recent Calexico earthquate some 130 miles south east of here. My main concern is that undue stress isn't being exerted on the copper tubing that could lead to a hidden leak.

majakdragon

Pressure on the piping should not affect the turning on and off of the valve since all the working parts are inside the valve. Probably calcium build-up on the stem or gate.

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Klawman

Calcium buildup would be great as I think it would be readily fixable. I loooked more closely and no longer think that anything is rubbing against anything external to the valve. I have been trying to remove the handle from the stem but it is on pretty good after 20 years and I am carefull not to pry to hard with screwdrivers. Is there a better way, perhaps something like a gear puller. Alternatively, is there any way of cleaning out internal calcium buildup without disassembling the valve stem?

I am attaching a picture of what I have and yes, I did remove the handle set screw.

Using a couple of screwdrivers for leverage, the handle is very slowly moving. I stopped for a break and look for something else to apply even leverage.

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Klawman

I got the handle off without damage to the valve assembly and took two photos. the first is terribly out of focus but I think the lower is helpful. For lack of knowing proper terminology, I will call the splined shaft that the handle fit on the stem shaft and the brass fitting it runs through the stem.

Note how the shaft isn't centered in the stem, but is off to one side so it almost appears to be up against the inside of the stem. After turning the stem with gas pliers I don't believe it in fact is binding against the stem.

From what you can see does anything indicate the cause of the shaft being so hard to turn? I am thinking that it somehow got bent. Possible from the quake. Should I attempt to remove the stem, which is pretty deep. I am concerned that since there is no way to get a grip on the valve assembly body too mush torsion may be transmitted to the connection with the pipes. If that needs be done, I don't see how a professional could do it either without opening up the tiled box surrounding the tub.

Should I leave well enough alone given that everything is working without a leak or even a drip as is? Thank you again.

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plumberinlaw

your problem is inside the valve assembly. Do you have access to the wall behind the valve assembly. Some houses will have a panel that can be removed or a wall in a closet can be opened up

Klawman

I can't think of a means of access without removing several tiles and cutting into the plywood tub surround. It is on the second floor of a two story with the far side against the rear exterior wall and the head against a side exterior. Another picture.

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plummen

replace the o rings inside the stem,or just buy a new stem.you shouldnt need to go into the wall any further than unscrewing the stem

Klawman

I think you are right and earlier today I dropped $6 on a shower valve socket wrench so I can pull the stem. I only tested its fit so far, as I have to schedule shutting down the water for the house with the family. including time to locate a replacement stem. Until I get it out I don't believe I will know if I can locate a replacement as the house is 20 years old. If not, I will rebuild it. Thanks

Klawman

So far pretty good. The stem came out with little effort pulling it from the top of the tub. Went to the HD and could not locate a replacement. The guy there also looked carefully and couldn't find one. It was really badly loaded up with calcium and he took his time to clean it as best he could with a box cutter. We both thought the o'rings looked pretty good and decided not to replace them for the time being. I bought some water proof grease to goop them up with.

It is now pretty well freed up but I believe the best think is to get a new one. Problem is what is it and whom to order from. Can you help me identify it. If it helps, the overall length is 5-1/4" and the water flow seems to be controlled by piece of ceramic that can rotate 1/4 turn inside the stem.

The house was built in 1991.

Meantime, it is back in and working silky smooth. Thank you all.

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plummen

id try relacing the o rings ,greasethe new ones up really good.
replace thewasher at same time as long as youre in there

Klawman

I put it back together for the time being and peace with the boss of the house, who wanted the water back on. If I can't locate a new valve stem, I will pick up some o rings. I am sure I will need them as now that I am aware of the problem with stiffening valves I notice that a cold sink valve of the same type in another part of the house is stiffening up.

What do you mean by the washer. After I put it all back, I was thinking how cheesy the seal was. Because of the cut out for what I will call a limiting peg (it limits the range of the turn to a quarter turn) I didn't want to use any thread tape and I didn't see a thin brass washer. I did check and watch for any sign of a leak and saw none. I wonder if there was a compression washer in place that I didn't notice and should have replaced. Is that the kind of washer you are thinking of?

plummen

is there a rubber washer on the bottem of stem held on with a brass screw?

Klawman

No. I found something on line that took a long time to look through (until I found out how it was indexed) and I think I have something similar to a Harden Ceramic part # 11-7859, but not it.

I am not sure what I am looking at, but it appears that the valve shaft can be twisted a quarter turn so as to rotate plastic (ceramic?) cylnder inside the bore of the valve body and permit water flow through when a hole bored cross ways through the plastic cylinder is aligned with a hole bored cross the mid point of the valve body. I am beginning to suspect that my valve stem is out of production and that my only option, short of tearing into the tub surround, is to replace the 3 o'rings and clean the inside of the manifold with some emery cloth so as to remove calcium.