The tools required to repair a Kohler toilet tank depends on the problem. Some problems with a toilet tank can be the tank itself that needs to be replaced, or there may be a problem with the flapper, fill valve or gasket. These different types of repairs require different tools for the job like a screwdriver, adjustable wrench or a sharp knife.
Fixing a leaky toilet tank might entail using an adjustable wrench and screwdriver to unfasten the tank bolts and separate it from the bowl. This is necessary to remove the old spud washer and gaskets that are causing the leak problem and should be replaced. If the problem is the flapper, then this a simple repair that requires a sharp knife to cut part of the rubber flapper off.