Pounding under the sink continued

[Adam Preble]

Awhile back, I asked about a pounding sound I got when running the hot water. It was like a rapid plumber's hammer. I thought it was coming from the header, but it sounds now like it's under the sink. The dishwasher is connected to the same mains, and doesn't cause the sound when run. Now, the cold water is beginning to make this sound.

The hot water starts to pound (~3 pounds a second) after a few seconds--about when it starts to get warm. The cold water starts almost immediately if the cold is opened very wide. If I close it a little, the pounding softens but the rate will stay the same. If I run the cold a little more closed, it doesn't happen.

What could possible cause this? Again, this doesn't happen with the dishwasher. However, if I start the hot water with it running, I get it, and sometimes it'll continue after I shut off the water. The only way to stop it is to stop the dishwasher, at which point it stops even if I restart the dishwasher.

I'm thinking it's time for a new faucet anyways but I'm not up for the replacement now. It's a ball-type faucet if that helps. I reached under and it doesn't look like there are any accessible nuts for tightening the pipe to it.

This all started after I replaced the undersink shutoff valves. I assume I shifted the copper pipes around a little bit and it's now causing some trouble. Could it be that I pinched the pipe someplace?

[Speedy Jim]

Does the faucet have a spray wand? If so, either the diverter valve (located in the base of the faucet) is bad or else the wand itself can be the cause.

If it's the diverter, replacing it may be easier than ripping out the faucet. The wand is even easier. Go to the Mfr web site support section for info on how-to and what parts.

Jim

[Adam Preble]

The diverter is bad; the spray wand doesn't deliver water at much pressure at all. I tried to replace the wand and it didn't help.

I can't unscrew the top of the faucet from its base. I've been through this before, but started to restrain myself when thoughts drifted to Dremeling between the top and bottom parts of the faucet based to hopefully dislodge it enough.

Is there some kind of silver bullet for loosening those up? I tried a plumber's wrench, but it was looking like I'd rip the whole faucet out rather than loosen the top half.

[Eigenvector]

I had a faucet in my sink that needed to be replaced. Turns out it was one of those single pipe jobbies where the faucet turned but didn't actually come off. I eventually took a hacksaw to the brass and cut the goddamn thing out and bought a nice new modern one that easily installed and only requires the water supply hoses to come off for removal.