Need some help with a leak in the hot water valve in the shower. It does not leak when the valve is closed, but leaks behind the valve when the hot or the cold water valve is opened up. It appears to me to be a pinhole, but I cannot see it. The leak is only behind the hot (left) even when the cold is just turned on. Thanks

Need some help with a leak in the hot water valve in the shower. It does not leak when the valve is closed, but leaks behind the valve when the hot or the cold water valve is opened up. It appears to me to be a pinhole, but I cannot see it. The leak is only behind the hot (left) even when the cold is just turned on. Thanks

Hey John,
"The leak is only behind the hot (left) even when the cold is just turned on."
Until I saw that I was going to instruct you on how to snug up the hot water bonnet packing nut.(Have you pulled the chrome cover plate behind the hot water knob and checked to see? ) But If you're sure the hot water side is off when you run cold water and it still leaks then the leak is got to be in the valve body or the shower raiser and about the only way to check would be to open up the wall behind the valve and check. Let me know what you find. Good luck, Tom