While trying to fix out sink sprayer, we needed to remove the faucet spout on our two handle sink.
Trying to get the spout back into place proved difficult. We could get it in place and run water without leaking, but the cap was too loose and moving the spout at all caused it to leak and be unstable.
We were able to get the cap tight, but it leaks water from the base. I imagine we might just need to replace the o-rings on the spout, but I’m more than a little out of my depth.
You might try using teflon tape and/or plumber’s putty, depending on which part is leaking. Both are cheap and readily available at hardware stores.
I’m not a plumber, but I’ve fixed several leaky faucets this way.
pipes that move need to be be sealed by something that will take wear and yet be soft enough to seal; this would be things like O-rings or plastic.
to seal you need things tight enough (to not leave a gap for water to leak) but not too tight (where you’ve squished something out of shape and created a gap for water to leak). this means that there are one or more things to tighten; not too tight, not too loose but just right, this might be 1/8 of a turn or less.
Moen, Delta and other common manufacturers are quite good about sending you specific parts or rebuild kits. If you call the manufacturer with a model number they should help you out. Common parts for popular models will be on the shelf at Home depot or plumbing supply houses.
Teflon tape or joint compound is meant for washerless threaded joints. Putty is used to waterproof imperfect mating surfaces between different materials; between a pop-up drain and a washbasin for example. Is isn’t meant for supply lines. Neither is meant for moving parts. Not a good fix.
Sounds like you needed to replace the sprayer diverter. If your faucet is like pretty much every other kitchen faucet I’ve worked on, there is an o-ring at the top and bottom of the faucet body, flanking the hole where the diverter lives. Your rings were probably almost worn out, and being pushed and pulled sideways when you removed and replaced the spout was enough to finish them off.
If you were able to handle replacing the diverter, changing the rings will be easy.
How old is the faucet? The recent ones have a cartridge that replaces the o-rings for the feeder lines, faucet, and internal valve. It’s like $10-15 or or so at HD and they are color coded.