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therink's avatar
therink
Explorer
Jul 20, 2013

Suggestions, re-installation of sewer tank Y fitting/valves

I just completed removal of the valves and 3" Y drain fitting on my black and grey tanks to remove debris from my black tank valve seat. My grey and black tanks are about 18" apart and the common 3" drain pipe enters up into the belly to a 3" Y fitting between the tanks. The drain pipe, Y fitting, and both grey and black tank gate valve flanges are one single piece (glued). I need to find a way to separate the tanks about 3/4" while they are in place to get the valve flanges to pop back into the tanks while keeping the o rings in place. This is not fun to do when there is residual tank water dripping in your face.
Anyway, the tank side walls have some flex and am thinking of gently lodging a couple 2 x 4's in between the tanks to push the side walls in just enough to get the flange lips to pop into place while being able to keep the o rings seated. I do not want to cut or replace the Y fitting and close nipples if I don't have to.
Anyone have suggestions?

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  • teddyu's avatar
    teddyu
    Explorer
    Jul 20, 2013
    Sounds like you have a plan. Lubricate the o-rings with plumbers grease and ensure they are seated in the grooves before insertion. Place a thin metal covering over the o-rings like a piece of thin aluminum over the opennings. Can't use to much grease in this case. Besides pushing the tanks apart, maybe you can also lever one elbow down while raising the other. Go slow, measure so you don't over extend, check everything prior to the final assembly, and keep your fingers from any pinch zone. Once the assebbly is in place, remove the aluminum coverings, they may be difficult to remove, hence the liberal use of grease. Before removing your blocking, start your coupling bolts. Good luck. JM2¢...

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