plumbing
I'm replacing my old kitchen faucet. Disconnecting the supply lines is no problem, but then I get stuck loosening the faucet from the deck. The lines go through a metal C-shaped washer-like thing, and I'm not sure what's holding it fast. I'm also not sure what to do with the gray plastic piece between the C-shaped piece and the sink.
Photos:
See the threaded tube? There's a nut threaded on that, which holds the plate in place.
Use a Basin Wrench (or any wrench you can fit in there) to loosen the nut (rotate the nut anticlockwise to loosen it), and the plate will slide out.
If the nut is stubborn, and doesn't want to budge. A good shot of penetrating oil can loosen things up.
In general, there's no problem using the main valve. However, if the sink valves are stuck, you might find that the main is also in poor repair. If the main is old and rarely used, you might find that's it's stuck or will become stuck once closed.
If the main valve is a gate/globe valve, and it looks old and cruddy. You might want to consider replacing that valve as well. I'd recommend replacing it with a ball valve.
Best Answer
Some interaction between the center threaded rod with the slot in it and the outer tube is what holds "C" clamp in place. I would try holding the center rod with a large flat blade screwdriver in the slot and loosening the tube with pliers by turning the rod CCW. If that doesn't work, then try turning the rod CW and see if this releases the outer tube.
The outer plastic nuts just unscrew.