I am looking to install a 3x3x2 wye to my horizontal drain pipe, which in turn connects to a vertical sewage stack. I am concerned that my 3" pvc drain pipe won't flex enough to allow connecting the wye. I haven't cut the drain pipe to attempt the install as I can't have the drain pipe down for an extended period of time. Any thoughts or suggestions?
Glue a couple of short pieces into the ends of the wye. Cut a section out of the horizontal drain about 1/4" longer than the over length of the wye with the stubouts. At that point you have a couple of options.
1) You can use a couple of slip couplings (AKA repair couplings). You'll find these at any plumbing supply house though I doubt you'll find them from HD or Lowes. These can be tricky if you've never used them before. Ask the folks at the supply house the proper method for use.
2) You can use a couple of no hub bands. I've seen these at the big box stores. If yours doesnt carry them a plumbing supply house will. These are quite easy to use and make for a relatively quick repair.