The first step in repairing a Kohler shower that doesn't shut off completely or continually drips or leaks is to determine the model number of the shower hardware you currently have installed in your bathroom. If you have the original manual that came with the faucet, identification will be as simple as checking the cover or title page. Alternatively, remove the shower head and take it to your local plumbing parts store to purchase the correct replacement parts.
Turning Off the Water Supply
Before beginning any work on your shower, you need to ensure that the water supply to the shower faucets and head is turned off. This may involve disengaging a localized shutoff valve that supplies water only to your bathroom or, as is most often the case, turning off the water supply where it enters your home. Leaving the taps open will ensure that most of the water in the lines drips harmlessly into the tub or shower pan.
Removing the Existing Hardware
A cushioning towel placed over the base of your bathtub or shower pan will protect the surface finish from falling parts and tools. By slipping a flat head screwdriver between the shower wall and the mounting caps, you can expose the screws that hold the hardware in place. You will need the right-sized screwdriver with the appropriate head to avoid stripping or damaging the screws. Removing the stem nut with an adjustable wrench or shower-stem socket wrench will allow you to free the shower hardware in order to diagnose the problem.
Kohler shower valves are screwed to the shower handle and may be removed by carefully lifting the entire assembly straight out from the wall. A quick look at the O-rings may reveal broken or cracked pieces that need to be replaced. If the rings look good, you may need to replace the cartridges or an entire shower valve. Taking the assembly to your local plumbing supply and repair outlet will confirm your assessment and allow you to pick up the right replacement parts for your Kohler shower.
If you are an avid do-it-yourselfer with the confidence to make repairs yourself, you can finish the replacement and restoration process, turn on the water supply and see if the problem has been solved. If the repair requires specialized tools and expertise, arrange for a professional to do the job for you. The same place that sold you the parts can book you a plumber or recommend someone that you can call in to finish the job.