Leaky hose shutoff

I noticed this morning that one of my hose outlets is dripping. I don't use this particular one anyway, and winter's coming. So, I opened the valve, went into the basement, shut off THAT valve, and found that it's still leaking outside 4 hours later. Great.
The inside valve looks pretty straightforward. The supply pipe is horizontal and the valve forms a "T". It's got provision for removal via wrench. (By the way, this is not a frostproof setup).
If I walk into Home Depot and wake up one of the highly trained sales associates with a 2x4 to the shins, should I, in theory, be able to walk out with another valve assembly? Or, am I just as well off to try changing the washer or whatever's inside?
Also: There's a tiny knurled knob on the side of the valve. What's that?
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Doug Kanter wrote:

holding the water in the pipe between the shutoff and the sill cock. Unless the shutoff is not closing properly, or the pipe is slanted down to the shutoff, it will drain eventually. If you decide to change anything to the supply, get a freeze proof sillcock. Lately, as things begin to break down in my plumbing, I have been changing screw type shutoff valves with the 1/4 turn ball valves.
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Bingo. The pipe slants down. But also, the inside shutoff doesn't have the soft feeling I expect from a nice, fresh washer. Hardened & worn out, maybe?
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have you tried repacking the valve with packing string?
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I haven't tried anything yet. Since every home repair that should take one hour ends up taking four times that long, I'm gathering ideas and waiting for the weekend. I've ditched the Home Depot idea, so I need to do this when one of the real hardware stores is open.
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That is the stuff to use to cure a leak around the faucet stem, not a leak from the pipe.
Harry K
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The "tiny knurled knob on the side of the valve" is actually a cap that, when removed, allows one to drain the pipe. WARNING- don't remove this cap while the valve is turned ON. Messy!

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OK - Here is what to do and not to do....
You probably do NOT need to replace any valves. You probably do NOT need to replace any packing as suggested. Joe F is correct on the purpose of the knurled knob.
You WILL need to shut off water at the main or some other up stream shutoff if you have one. On the inside shutoff, the one next to your hose bib, loosen the main packing nut, below the handle, remove the stem. Lefty loosey, rightey tighty. You need to replace the washer at the end of the stem. (Bring stem with you to store ensure you get correct size) You may also need to replace a deteriated washer screw (can be a PIA, been there). Replace stem and tighten nut. Repeat for the outside bib.
This entire endeavor should not cost you more than 25 cents. $2.50 if you need some packing too (See below on what can go wrong). Should take you only a few minutes.
I measure project complexity by number of trips to the store. This is most likely a 1 trip job.
Things that could go wrong.
- Main will not shut off and begins to leak between stem and packing nut. Will possibly require water co to shut off at street. (Worst case scenario) - New washer does not solve problem - Then its probably a damaged seat (where the washer seats inside the valve). Some can be replaced with a special tool, some cant. New valve probably costs the same as a seat tool and new seat. - You end up with a new leak between the stem and cap nut - You also need to replace packing, under packing nut, another trip to the store.
Good luck, have fun.
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OK. This is identical to my old two knob bathtub faucet, but vertical instead of horizontal.
Here's MY worst-case scenario: Regardless of the care taken, the removal of the packing nut torques the pipes just enough to crack the solder joint. Hello plumber. Goodbye $98.75.
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Freezeproofs have washers just like any other faucet. Unscrew it, pull out the LONG shaft, and replace the washer....
The little tit on the side of the valve is to drain the water out of the line.
On Wed, 13 Oct 2004 17:49:33 GMT, "Doug Kanter"

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That is cap on a nipple - loosen it and air is allowed into the pipe to assist draining.
Re 'provisions for removal'. In a run of pipe, to remove something in the middle you need a union somewhere in that run. The procedure is to break the union then unscrew the item to be replaced. Apologies if you already knew that.
Harry K
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