These are notes from Jan 2023 me to future me – here’s what you need to know:
- To fix the 2007 Pegasus [is that a Home Depot brand?] widespread two-handled faucet on the upstairs bathroom sink
- About fixing leaking sink faucets more generally
Diagnosis. Figure out if the hot or cold is leaking by turning off the water supply lines one at a time.
The part to change to stop the dripping is the cartridge (in a one-handled faucet) or, in this widespread two-handle bathroom sink, the faucet stem. It comes with a new retaining clip. Cartridge vs. faucet stem is mostly a matter of terminology.
Removing the handle. The faucet stem will be accessed via the top of the sink, i.e., the handle has to come off. Leave the stuff under the sink alone, except if you need to loosen a retaining nut or screws to rotate the top assembly into a better angle for accessing a set screw.
If there’s no set screw to undo, try to pry a cap off to access one. Mine is the little bit on the end. Under that, loose the set screw holding the handle on. Then pry the handle off. In my case, it was extremely stuck, and it felt like the wrong move to pull that hard without getting results. But indeed, I was able to pull it straight up. Take care not to mar the finish, by putting something rubbery on the handle before you clamp it to pull.
No wonder my handle was so hard to remove – minerals had gunked everything up!

If your faucet is full of mineral deposits like mine, soak it in white vinegar while you go to the hardware store for the new faucet stem.
New faucet stem selection. Choose the new faucet stem based on visual match to the old one, most of all the spindle in the middle where the handle socket fits onto it. I was sold the wrong faucet stem (Danco 3Z-16C) at store #1 because the brand matched (“Pegasus”) and the salesman thought it wouldn’t be a problem that the spindle was star-shaped and lacked a flat side. I should not have listened to him.
If you look at reviews for that stem online, a third of them say it doesn’t match on the user’s Pegasus faucet. And indeed, the correct replacement stem for my Pegasus – model unknown, installed in 2007 – was a Danco 3S-11C, despite not being listed under Pegasus. Note that hot and cold-side faucet stems are different, that’s the last letter in the model number.
Lube the new cartridge before installing it and tighten down properly. Tightening the hex ring (which I replaced, the old one was pretty beat-up and it was just a few bucks to swap out) with channel lock pliers threatened to deform it, it’s a flimsy piece. So I switched to my biggest deep socket wrench and tightened it by hand. I think it was 15/16″ ? I didn’t use the socket wrench handle, I just held on to the socket and hand-twisted.
After I got everything reassembled, there was still a slow drip. I took it apart again, greased the cartridge with silicon diver’s lubricant, and put it back together. No drip. Here’s the new stem installed (note the vinegar soak has cleaned off the screw):

Replacing the o-ring under the handle. There was a white plastic gasket immediately under the handle, now terribly flattened and misshapen. I replaced it with an extra black o-ring I had, meant for a ball-lock beverage keg liquid quick-disconnect assembly. Ideally I would have made this change on both handles so it matches, but it’s such a thin o-ring and it’s covered up by the handle so it’s not really noticeable.
Possible downside to the fix: faucet handle travel range. The only lingering problem with my fix is that the travel radius for the new faucet stem is greater than the original. Now the original hot stem travels about 80 degrees from off to full, while this new cold stem travels about 90 degrees. I could replace the hot-side stem too and hope that the replacement model from the same brand would provide a similar increase in travel range, but that’s not worth the time since my hot-side handle is also corroded in place and doesn’t want to budge. I’ll just live with the handle angles being slightly mismatched…
… until the hot side faucet stem starts dripping and I have to replace it too. I hope that when that day comes, I remember that this blog post is here!