Leaking Angle Supply

I have this angle supply: http://www.us.kohler.com/onlinecatalog/detail.jsp?item=430302&prod_num=7637

The angle supply has leaked gradually from the nut that clamps down on a brass sleeve, securing the vertical supply tube to the valve. I disconnected and reconnected the supply recently, and now I have water spraying vertically from the nut when I open the valve. What do you think the problem is?

I don't know what the problem is with this valve, but if it was mine, I'd replace it with a new 1/4 turn valve. They are far superior to the old many-twist type. Toilet supply valves should always be full on, so there is no advantage whatsoever to having to make several turns on the valve. The 1/4 turn style are much easier to turn off when necessary also. They come in every connection configuration, so fitting will be no problem.

With a compression sleeve and nut for a toilet or lav, tighten the upper nut first, that is a face to face seal.
Then the lower nut should be tightened. If it was done in the wrong order, it may be that you can't pull the nut down tight to the sleeve.
In that case, buy a new brass sleeve and supply tube, and start over,
Tighten the top first, and lastly, the compression but below.

If you have a braided supply with rubber seals, then you do the lower one first, and then the top.

Thanks, guys. These $125 angle supplies with the fancy finish hit the wallet a lot harder than a braided hose. I'll report back.

It is also possible that the compression fitting was overtightened, which will deform the ferule and tube and cause a leak. I would replace the tube and ferule and see where that got me.

I'm offended that you would suggest I might overtighten my fittings. I do recall having to crack the nut loose with vise grips.

Well, I can tell you the stops I referred to certainly do not cost $125! I don't recall exactly how much I paid for a couple I bought awhile back, but likely around $8 or $10. Of course, if it's important to you to be able to tell people you have a $125 stop on you potty, then go for it. LOL

But, on the other hand, if you didn't need a wrench, it was not tight enough. A compression fitting requires intimate metal-to-metal contact and some slight deformation to seal. Too much, and you exceed the resilience of the metal, and it is permanently deformed, not enough, and it leaks.

The Vibrant Brushed Nickel is Model Number: K-7637-SN, List price*: $173.15

http://www.us.kohler.com/onlinecatalog/pdf/115090_4.pdf

So, I'm finally ready for drywall in the bathroom. Now that I have to secure the valve to the blocking and close things up, I want to make sure the height is correct. How do these steps sound?:

1. Bottom out the vertical tube in the valve without tightening anything
2. Adjust the height of the valve so the flange on the vertical tube is within about 1/8" of the ballcock
3. Screw the PEX drop ear elbow to the blocking
4. Remove the tube by rotating the valve counterclockwise and attach a supply hose to temporarily supply the toilet untill the drywall goes in
5. Before drywall installation, remove the horizontal pipe and valve
6. Drill a hole in the drywall and replace the horizontal pipe
7. Replace the hose with the vertical tube by rotating the valve counterclockwise until the tube can be inserted
8. Rotate the valve back into position
9. Tighten the white plastic retaining nut to snug up the top flange of the vertical tube with the ballcock
10. Tighten the lower nut on a brand new ferrule until the water stops leaking

the height is not so critical, as you can cut the riser to length. More importantly, a compression joint like that, the tube has to enter straight in. If the valve does not line up directly under the toilet fitting, you have to do some fancy tube bending to offset the riser. This is the reason most plumbers gave up on fixed risers years ago! Frankly, the average plumber, certainly yours truly, has done so few of those that it adds a lot of time to a job to get one right!

The thing that makes those valves so expensive is the name KOHLER on them. Any other name and that same valve would be about $60.00.

Are we talking +-1/8" or +-1/16" tolerance for the vertical alignment between the riser and the ballcock nipple?

I can see why these things are not cost effective for a plumber to install . I can't get overtime at my job, so my opportunity cost is a lot cheaper than that of a plumber, plus I don't have to pay any taxes on work I do for myself (at least until someone decides to change the capital gains tax rules on the sale of a home). As far as the price of the Kohler stuff is concerned, I usually find a good deal after watching the usual sources for a few weeks.

The ball cock nut gets tightned first, and then the compression at the bottom.
The lower seal can slide up and down before it's snugged. The top one, is a flat surface that needs to mate up.