Re: Tub faucet leaks when shower is on
The diverter is an easy repair and works just like the normal hot/cold valves with a rubber seat. Remove the stem and you'll find the rubber washer held in place with a screw. Remove the screw to replace the washer. Reassemble the valve and you're back in business. The diverter isn't hooked up to any pressurized supply, that is the job of the hot/cold valves. The diverter merely changes the water flow from the tub spout to the shower head. I would also recommend Googling your valve brand and finding the manufacturer's repair manual on it. This will provide an exploded view of the valve to give you a good idea what you're getting into and how to do the repair.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!