leak in Delta 13 series shower

[Bob in NH]

I have a leak in a Delta 13 series single knob shower control. I have replaced the little rubber seats and springs, however when it was put back together, the mixer housing (white plastic part) was put in backwards, and the person who did it cut off the little triangle tabs to line up with the slots in the pipe. I took it apart again to put the white plastic back on correctly and now it leaks worse.

I think what might have happened is the cartridge that goes behind the mixer valve and into the water pipes, I think this may have moved. The drip leak is now almost a steady trickle, and its hot water.

My suspicion is the cartidge between the mixer valve and the pipe is not seated all the way into the pipes and/or the o-rings on the back end of this need replacing. When we originally took it apart to get to the seats I didn't realize this part could come out as well.

Does this make sense? If so, how do you get that cartridge out of the pipe? I am not a big fan of using force to get things apart when I am not sure how they are suppose to come apart. Looks like i might just need to grab it and pull, but not sure and don't want to break anything.


Thanks for any advice you have!

--Bob

[BAPlumber]

If i'm reading this correctly, the plastic cartridge should just pull out.
http://www.deltafaucet.com/media/Pro...13422_c6d1.pdf