I have the same problem as several others. It is always best to Start from the beginning. The shower head was leaking: I replaced the valve stem assy, essy-peasy, installed the same as the old one. The handle travels appx. 150 degrees counter clockwise. I have read the forums such as this one. At one point I was getting reversed hot & cold water. I read where I should turn the valve stem 180 degrees, this did not work either It reversed the direction the handle travels. I got a cartridge 974-042 that was no better. Today reinstalled new oem parts as originally installed and no hot water.