A: Mike, I can tell that you are a pretty experienced handyperson, but it looks like you might have to get a little help with this one.

What you have is one of the old-style compression tub and shower valves. These valves have three handles: the middle handle is the diverter for the tub and shower, and the hot and cold valves are on either side of the diverter.

The main problem with most of the three-handle type shower valves is that there's no scald protection. They directly mix water just like most sink faucets. Modern tub and shower valves use a one handle setup with built-in anti-scald protection.

I appreciate the work you must have put into this project by locating the older parts and the fact that you were able to install all the parts. However, due to its age, continued leaking, and the issue of updating to one-handle anti-scald technology to meet most local codes, I recommend that you install a new valve.

This job can involve opening up the back wall or access panel; cutting off the old valve from the water lines, tub spout and shower pipe; removing tiles and backing from the shower wall to fit the new valve; and reinstalling the water lines, tub spout and shower piping. Then, trimming off both inside and backside walls to finish the job. Whew!

In the long run you will be safer in the shower and you'll add resale value to your bathroom. As I mentioned, you may want to call in a licensed plumber to help you out with this one. Most good plumbers can give you a price up front for this job and be in and out fairly quickly with no major disturbance to your bathroom. Just make sure you get everything promised in writing so you won't end up getting "soaked" on this tub and shower job!