Why this happens

Delta's guidance for a single-handle kitchen faucet drip says the seats and springs wear with normal use and need replacing occasionally. Two rubber seats, each on a tiny spring, press up against the ball; when they flatten, water sneaks past with the handle off. Delta also suggests removing the aerator and flushing the faucet for a minute first, since debris can hold a seat open.

How to fix it

Shut off both stops under the sink and open the faucet to release pressure. Close the drain.
Remove the aerator from the spout tip, turn the water back on briefly to flush debris, then shut it off again.
Remove the handle set screw, lift the handle, unscrew the cap, and lift out the cam, ball and the two seats and springs beneath it.
Set the new springs in the holes, press the new seats over them, and reassemble in the same order. Delta's RP4993 kit includes two sets.
If the ball itself is scored or the drip returns, replace the ball too. Delta says a damaged stainless liner in the body may mean replacing the faucet.

The part that fixes it

Replacement for Delta RP4993 Seats and Springs, 24 Pack

24 pack on Amazon

FourHome is our own brand of replacement parts; this site is published by the team behind it. We earn from purchases made through this link.

Not sure which part you have? Pull the old one and match it by brand, length and broach on Stems & Cartridges, an identification index of faucet stems and cartridges by part number.

If this does not fix it, tell the plumber

It is a single-handle ball-type kitchen faucet dripping from the spout.
Whether you already replaced the seats and springs.
The faucet's age and whether the ball looked worn.

Build the full list: what to tell the plumber.

Start this troubleshooter over

References (every fact above comes from one of these pages)

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