My tub faucet was leaking and I replaced the cartridge (took me all day to figure it out!) Now I only get lukewarm water. I've read the other posts on this repair and my faucet (when it worked) used to pull out and you would turn it one way for hot, the other for cold. Inside the handle is one plastic piece that is a circle with the sides cut off, this fits over the cartridge stem and into the faucet handle. Have I installed the cartridge wrong?

Any chance of a pic?