Water doesn't switch completely to shower head
I just move in a house that's pretty old. I notice the water doesn't switch all the way to the shower head. More so hot than cold but still both. It still runs out of the faucet while partially running from the shower head also. How do I fix this problem? I can remove the hot water cap but the other are stuck so I know I'm going to need a handle remover.
One more thing what do I use to properly clean all the old or corroded parts so it doesn't happen again and to insure the knobs don't get stuck if I have to remove them again.
Thanks in advance