I am trying to replace a kitchen faucet but my water shut-off valves under the sink are jammed. They just won't turn. I even tried spraying some WD-40 on both the hot and cold water valves but to no avail. I then tried shutting off the main line but it seems like that does not close all the way as once I shut it all the way and ran a faucet to drain the water it kept coming at a slow pressure for like 15 minutes which seemed kind of long. Any suggestions would be greatly appreciated specailly on how to loosen the shut off valves under the sink.

I am afraid there is no absolute answers here Hasman:

Sounds like shutoffs are getting old and should be replaced altogether. It also sounds like you need to call the town/city water department and have them shut the street water supply to your house off while a plumber comes in and replaces the main shutoff. At that time, plumber can install new shutoffs and then you can install kitchen faucet yourself ;)

Main shutoffs are not something to take lightly... the day a pipe breaks in cellar unexpectedly will be the same day that that main valve fails worse then it is now and floods the place or certainly frustrates the whole situation as the town/city people have to treat as emergency, plumber's waiting hours for them to show... etc. etc.

That being said... you may be able to tweak those handles under sink by removing the handles with a screwdriver, then using 1 plier and 1 wrench, hold shutoff with wrench and then using pliers, grab the exposed stem head and give it a turn clockwise to shut off. As long as holding against yourself good, can give a good turn with pliers.. ok?

Note here that you may get these to close... getting back on probably won't be bad... but you will need to be aware of the packing nut at end of the shutoff (see pic.). Here, after shutoffs turned back on, will need to tighten the packing nuts by turning 1/8th to 1/4 turn... may need to hold against yourself again. BUT.. sometimes you can't tighten the nut anymore.. and then... WELL.. Like I said... these should have been replaced... ;)

They make some really good compression stops for under sink if you want to try to cut off old shutoffs yourself. Here, shut main, let trickle into lowest faucet in house.. if no water at kitchen sink, then cut off a shutoff and quickly install the compression shutoff (see pic.#2 and 3). These shutoffs tighten on hand tight plus a full turn or so with pliers. They are remarkably reliable. JUST BE CLEAR that when you cut shutoffs off you could be opening Pandora's box.. ok?

Gave you as much as I could... you decide. Let us know your decision.. we are glad to help if we can... Mark

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