I have Kohler bathroom faucets with separate handles, and the only way I was able to remove the cold cartridge, was to remove the cold water valve assembly.
Kohler GP77005-RP Hot Ceramic Cartridge |
Kohler GP77006-RP Cold Ceramic Cartridge
I removed all the tubing, handle, chrome, nut, washers, until I had just the valve assembly with the cartridge at one end. I took a roll of masking tape and wrapped the valve body threads several times. I found my ratchet wrench with a 5/8" spark plug socket (or deep socket will work too) and took these tools and the valve to Home Depot. In the plumbing department, I found a 2 foot pipe wrench and a 2 foot section of steel pipe. This rather large pipe wrench goes around the valve body, (masking tape protects the threads), and I put my socket over the cartridge and the piece of pipe over the ratchet handle. Then it's just a matter of applying enough force to remove the cartridge from the valve body. I have had to replace my cold water cartridges several times, due to all the Kohler faucets in my place, and it has worked every time for me. Thanks to Home Depot for letting me borrow their stuff. (Even though they were unaware, lol)
Alternately, you can buy the complete valve assembly as a part, but it will have half the flow rate of the pre-2010 Kohler valves. (And costs 3x more)
Kohler 1131482 Cold Ultraglide Complete Valve Assembly
Kohler 1131481 Hot Ultraglide Complete Valve Assembly
I got the cartridge off Amazon, since Home Depot doesn't sell Kohler parts. I have yet to replace a Hot cartridge, it seems only the cold ones leak at my place