I have a Kohler kitchen faucet that I bought at Home Depot and installed myself a few years ago. It is "Forte single-control kitchen sink faucet with sidespray and lever handle" (model number K-10412). The support page for this faucet is here:

Kohler Plumbing

Clicking on "Kitchen Faucets" gives a detailed diagram of the faucet assembly:

Kohler Plumbing

For some time now, the faucet has leaked water from the bonnet. The leak started a couple months after I installed the faucet. The leak gets worse if I push down on the spout and seems to dissipate if I lift slightly on the spout. I called Kohler to complain (at the time the faucet was still rather new) and they sent me the following parts:

1016515 -- Valve Kit
71117 -- Bearing, Spout (Qty: 2)
71118 -- O-Ring (Qty: 2)
75878 -- Diverter Assembly
1045715-P -- Packet, DC-111 Lube

That was February of 2007. Now it is almost two years later and I am finally getting around to trying to fix this leak.

I have the faucet disassembled now and I'm not sure what the problem might be. Nothing looks broken. I removed the two O-Rings and the two spout bearings and they all look okay. I can replace them with the new parts but will this fix the problem? The valve kit has some dark almost charcoal-like substance on its stem but I'm not convinced that this is the cause of the leak either. Any thoughts?

Separately, the diverter assembly looks like this:

Kohler Plumbing

It is located in the back of the body. I don't have a lot of room to figure out what's going on back there because the body is only a couple of inches from a tile back splash. I can't figure out how to remove the existing diverter to replace it with the part Kohler sent me. The side sprayer works fine so I'm not even sure that this part needs to be replaced.

Any thoughts on what could be causing water to seep up into the bonnet? And if you recommend replacing the diverter, how do I remove it? Thanks.