leaking shower drain

[inspectorgf]

I have a leak at the shower drain where the drain sits against the shower floor. I have a sierra 5th wheel. A friend of mine had plumbers putty so we took it apart and tried to reseal but didn't have the tool to hold the drain still. It held for a shower or 2 and started leaking again. I then took it to the dealer and they resealed it and put silicone over the drain. It started leaking again after 5 showers. I then pulled it apart again cleaned everything really well put plumbers putty on again and got the tool to hold the drain from spinning and had my wife hold it while i tighten it from below. It is just a plastic drain with a plastic nut that you tighten by hand. It is not leaking now but I have only used it twice. I did notice when an adult gets in the shower the floor pushes down and of course the pipe with it. I assume it has always been like this. There appears to be no way to brace the floor as you only have a hole cut for the drain. Just wanted to know if it sounds like I fixed it right this time or if there is something else to do. Its in an area where I have to keep a panel off in the pass through storage to keep an eye on it so I can't keep that panel off forever.

[Duckogram]

Been there, done that. The flexing of the floor causes the drain to loosen. You must eliminate as much of the movement as possible. On my Coachmen, I tried what you did with the same results. Then I went to ACE and got a rubber gasket, gave it a very very thin coat of silicone grease so it would not bind, tightened the nut as much as I could. Let it sit for a day, then retightened it. Then I braced the floor of the shower. On my current unit, I did not wait for the leak. I just tightened every fitting in the unit and braced the floor before my Cartmen girth caused it to leak. I never had another leak in the Coachmen and the Sunseeker has never leaked. Here’s what I did:
http://www.forestriverforums.com/for...ml#post1732451

[A32Deuce]

Can you get foam under the pan to stop downward movement? I did on mine to stop it. Used that thick shipping foam they use to protect during shipping. That way if you have to do anything under the pan, you can remove the foam.

[inspectorgf]

Thanks for the advice. On mine there is a piece of foam between the pan and plywood then another large piece of foam between the plywood and the trim paneling you see and there is a hole cut through all of that for the drain. So I can not brace it as in the first response. The foam underneath the pan does not run all the way to the opening on 1 side so I have thought about trying to push some more foam in there.

[inspectorgf]

Also I have 4 heater tubes from my furnace that run below the shower drain making it impossible to put any boards in there. I have a 5th wheel so there is a lot of space between the bottom floor and the floor the shower sits on.