I changed my one handle shower cartridge by moen. This was not easy and had to break it apart to remove. I put a new one in and there was no pressure. I changed this one and got very little improvement. I had great pressure before it was just leaking any ideas??

When you removed the previous cartridge you turned it too far as you rotated it trying to pull it out and left some rubber debris. Simply disassemble and remove the debris in the ports.

when ya removed the previous cartridge ya turned it too far as you rotated it trying to pull it out and left some rubber debris. simply disassemble and remove the debris in the ports.
Your right it was a blockage but in the shower head thanks you damn yankee

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