I just installed the Moen T2153 tub/shower fixtures. I'm having trouble with the bathtub spout. It is a slip tube application in which the spout 'slips' over 1/2" copper tubing coming out of the wall. When I pull up the lever on the spout to divert water to the shower head, water comes gushing out the back of the spout at the wall instead.

You need to remove the spout and inspect it. Sounds like the slip washer is not making a good seal. Also slide your fingers all around the copper pipe to see if you have any nicks or debris on the pipe. Did not water at all come out of the shower arm?

Aedurham,

Follow Ballenger1 advice you will be OK make sure you check the O ring for any damage if you see any replace the O ring and I would suggest to lnbricate the O ring before installation, Good luck and happy New Year.

John