kep1113 wrote:

I have searched this group for answers but haven't been able to find
my particular problem. Hopefully, someone can help!

We have a Delta kitchen faucet - a model with two handles, a tall
spout, and sprayer. A leak has developed somewhere, but I can't find
the source. The first time I noticed a leak, water was dripping from
beneath the hot water-side locknut. I replaced the stems, seats and
springs on both sides and turned the water back on. At this point
everything seemed fine. A few days later I checked and it was leaking
again, this time from around the cold-side lock nut.
At this point, I disconnected the faucet, brought it under the sink
with me and reconnected it so that I could try to see where the water
is coming from. Of course, no water leak. So . . . I reconnected
everything, waited a day, and PRESTO the leak reappears.

Before I spend $100 replacing this faucet, could the o-rings beneath
the spout be causing this problem? It seems like if they were bad,
the faucet would leak around the base of the spout, not under the
sink. Can these faucets just develop a leak somewhere besides where a
gasket or o-ring is?

Any help would be greatly appreciated!!

You're right; spout seal leaks should be visible on top.
But they can be tiny and you may not see them before the
water runs underneath.
If you're 100% sure there are no leaks on top, and the water
isn't coming from the spray hose/wand, I'd suspect a tiny
flaw in the casting underneath. Rare, but possible.
Jim