Leaking PVC to Cast Iron
#1
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Leaking PVC to Cast Iron
So I'm trying to fix the plumbing under my tub. Just put the new tub in (with mortar base) and took some of the old plumbing connected to the drain assembly out as well (it was old and off-center). Problem now is I can't get the threaded PVC connection to the this cast iron or galvanized thing - I think it's a cleanout. Anyway, I've tried using teflon tape, a couple different pipe dopes, and even tape with dope. Closest I got was Teflon tape for gas lines but there was still the smallest amoutn of water coming out. I've also used different PVC connectors just to make sure it wasnt that.
Anyway, this is driving me nuts. I can't take this cleanout or whatever it is out because of the existing subflooring, pipework, and now the tub. In theory I could maybe cut it off at the connection to the rest of the plumbing, but there's no guarantee once I remove that the next connection won't do the same thing. Everything and everyone I've read or talked to has said tape or dope. Some say more, some say less so I've done both. Any advice?
Anyway, this is driving me nuts. I can't take this cleanout or whatever it is out because of the existing subflooring, pipework, and now the tub. In theory I could maybe cut it off at the connection to the rest of the plumbing, but there's no guarantee once I remove that the next connection won't do the same thing. Everything and everyone I've read or talked to has said tape or dope. Some say more, some say less so I've done both. Any advice?
#2
I'm not a plumber.... just a DIY'er. I would try to cut the pipe between the Tee and the drum trap..... as close as possible to the trap so that there was a place for a pipe wrench to grab on. The drum trap needs to go. It would be great to just unscrew it but we can see that can't happen. Actually, had I been doing that.... the water pipes up the wall would probably have been replaced too.
That looks like old iron and with age comes rust, corrosion and inside restrictions.
Water lines as well as drain lines.
That looks like old iron and with age comes rust, corrosion and inside restrictions.
Water lines as well as drain lines.

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Thanks! Yeah in retrospect I probably should have done that, but this was one what looked like about 5 or 6 tiny jobs that went into getting the tub in and tearing out that pipe and opening up the floor would have been a hell of a lot of work. Hindsight is 20/20 but the mortar is set!
#4
Welcome to the DIY world. 
I don't know if there is a fitting that will connect directly to the drum trap. I have a feeling the answer is no... which is why I recommended removing it.
Others will stop by and comment.

I don't know if there is a fitting that will connect directly to the drum trap. I have a feeling the answer is no... which is why I recommended removing it.
Others will stop by and comment.
#5
I would probably try TFE paste, it's very thick. You could also replace the drum trap with a new one (special order but available they menards)... assuming your code even allows them now days. I have never run into them in this area.
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Tried TFE Paste, two other pipe dopes, plumbers tape, the tape you you on gas lines... I tried a few of these combined, too. Anyway, none of it worked. Guessing the drum trap's threads are just messed up or something. So unless somebody has something out of left field I guess I'm getting an arm workout. Thank you again!
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hardly any space between the joists. I honestly don't know how they got the pipe in they had there. Even with 1.5 inch 90 degree pvc it's a really tight fit. probably just need to get it out of there.
#9
The problem with drum traps is that they need to be manually cleaned out. There's a cleanout plug on top and the gunk and hair and whatever need to be cleaned out occasionally. P-traps are 'self cleaning', so they typically don't need to be cleaned unless they are specifically clogged. That's another good reason to figure out how to get rid of the drum trap.
I know it's a pain, but it may be worse a year or two from now.
I know it's a pain, but it may be worse a year or two from now.
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Drum Trap Out, New Problem
OK, so Im obviously a novice here. I got the drum off pretty easily with a sawzall. Cut it as close to the trap as I possibly could so I could get hold of what was left with a pipe wrench. Before I started, I lubed it up with liquid wrench, then tried to get it turned with a pipe wrench. Repeated that process (lube, then wrench) about 3 or 4 total times. All that's happening is the pipe's getting bent. There's some old pipe dope or something on it and it;s heavily rusted. Any advice beyond lube/wrench?
Oh and I have no idea what the pipe coming off the top of the t-fitting is attached to. I don't have any plumbing above the tub you can see. To get that out I'd also have to tear out some ceiling and walls and basically replace the whole shebang, which is where I'be be going at that point. . I'm also, ya know, a total novice.
Anyway, thanks again for all the advice. A magic bullet on this stuck pipe would be awesome!
Oh and I have no idea what the pipe coming off the top of the t-fitting is attached to. I don't have any plumbing above the tub you can see. To get that out I'd also have to tear out some ceiling and walls and basically replace the whole shebang, which is where I'be be going at that point. . I'm also, ya know, a total novice.
Anyway, thanks again for all the advice. A magic bullet on this stuck pipe would be awesome!
#11
Keeo at it! The worst that will happen is that the pipe stub will break and you can remove it in pieces. (You could also cut pieces of the stub and chisel them out.) Just be careful not to damage the internal threads of the tee. You should then be able to screw your replacement fitting into the tee after cleaning the threads with a wire brush..
The pipe going up is most likely the vent line.
The pipe going up is most likely the vent line.
#13
I hate to be the bearer of bad news... but where's your trap?
You've sort of created one with some elbows, and maybe that will work, but typically, you'd use an actual 1.5" PVC trap under the tub. Maybe one of the more experienced plumbers can tell whether these elbows would pass for a trap.
You've sort of created one with some elbows, and maybe that will work, but typically, you'd use an actual 1.5" PVC trap under the tub. Maybe one of the more experienced plumbers can tell whether these elbows would pass for a trap.