The diverter tub spout in your bath/shower assembly makes bathing or showering very convenient. If for some unforseen reason you find that your diverter tub spout stops working properly, you should consider repairing it yourself before calling in a plumber. Following these directions will help you to accomplish this task.
Step 1 - Expose the Diverter Assembly
Feel around the faucet near the wall on the bottom side and locate the indention that holds an Allen screw. You may not find one, as many faucets just screw on and do not have a screw to hold them secure. If you do find an Allen screw remove it with the Allen wrench then either pull while gently twisting or unscrew the spout to the left to expose the diverter. The lever that is on the spout stays with it so you don't have to worry about removing it.
Step 2 - Repair the Faulty Diverter
Locate the rubber washer and replace. This removes the potential for leakage. Go through the diverter assembly and lubricate all moving parts to ensure proper motion and use. It is important that all parts work without friction to ensure proper movement of all parts.
Step 3 - Replace Diverter (If Necessary)
The diverter most likely will not need to be replaced but instead maintained by lubrication and replacement of any washers in the assembly. If the diverter does prove to be broken and not merely in need of maintenance then it is very possible to replace all the parts of the diverter with a little information and the instructions that came with the diverter kit from your local hardware or home store.
Step 4 - Reassemble
Reverse the above instructions to reinstall the parts of the tub. Verify all moving parts are working, screw the spout back onto the assembly and turn on the water to be sure that you do not have any leaks. Do not put the Allen screw onto the spout until you've verified that there is no longer any leaks around the pipes or the rubber washer that has been replaced.
Things to Consider
When repairing the diverter assembly in a tub it is not necessary to turn off the water to the home because the diverter is located on the dry side of the plumbing fixtures in the tub. Do not turn on the water faucets in the tub while you have the faucet removed and the diverter exposed. If you do you will cause water to spout from the pipe into your home instead of through the intended water path.
If your repairs appear to be more serious than gaskets, washers, and lubrication, it is possible for you to purchase the entire universal tub spout kit from your local hardware or home improvement store. Most of these kits will come with instructions on installation and proper workings of the moving parts.