PVC / Plumbing Question - Page 2 - PeachParts Mercedes-Benz Forum

gmercoleza · #16 02-23-2007, 10:12 PM

Pipe above carries waste, as there is a sink on the other side of the wall whose 1 1/2 inch P-trap feeds into this 2 inch pipe using some sort of reducer.

Just got back from HD, the plumbing guy there was pretty stumped and they don't make any internal coupler like I described. His suggestion was to cut flush with the bottom plate, then cut through the plate on both sides of the pipe as far away from it as possible, then lift the resulting square donut piece off. That should leave a stub roughly 1 1/2 inches long (the height of the bottom plate).

I think at this point I don't have many other options, so I will give it a try tomorrow.

kerry · #17 02-23-2007, 10:40 PM

I wouldn't do that myself. Once you cut it flush at the bottom plate, you're screwed if you can't get a coupling on it. (I'm assuming all of this is on a concrete pad with no access below at all) It's worth a half hour's effort to try to separate the two 45's before cutting it at the baseplate.
Is there a toilet in the vicinity? Can you tie into the toilet drain? I bet someone makes an adaptor that lifts the toilet off the floor 2 inches and allows a drain line to feed into the bottom of the toilet. You could then run the drain from the shower around the wall just about at floor level to the back of the toilet.
Barring that, I'd actually raise the shower up higher to tie into that line before cutting it at the baseplate.

Chas H · #18 02-23-2007, 11:36 PM

You need a reciprocating saw (sawzall) to cut thru the floor. A cut on each side of the pipe back out to the new drain location will let you peel up the floor and get to the existing drain. Cut the existing drain at the proper level and glue in your "T". Can you lift the existing above drain pipe after it's cut to allow inserting a "T"?

t walgamuth · #19 02-24-2007, 04:07 AM

well, a recip saw will be tough since he is dealing with concrete.

imho, doing it properly is the only way to go. putting in a shower that has its floor 8" or more above the adjoining floor will look like you couln't figure out how to do it the right way.

i would either bite the bullet and break out the concrete and put in the joint down where it should be or forget about the shower.

having a makeshift shower setup like that will seriously devalue your home, imho.

breaking out the concrete will be messy and not easy but in the end will really not cost much money.

there is no substitute for doing it right in the first place.

that is why we all drive benzes, no?

tom w

Wodnek · #20 02-24-2007, 07:58 AM

If you heat it up good with a heat gun, you may be able to get it apart.

They make something called a star drill. It is like a chisel but made for breaking up small areas of concrete without the dammage spreading. A 1/2 inch star drill should make it possible to expose just an inch of the pipe.

Southern · #21 02-24-2007, 10:01 AM

I showed the picture to my son who is a plummer. His first comment was why don't you just break-up the concrete floor and do it the proper way? He does this all the time using a hammer & chissel to bust up the floor and use a bag of concrete mix to patch it up when done.

He said that you can peel back the existing PVC pipe but he recommends that after you cut the pipe, use a sawsall to cut a notch, heat it up with a torch and use a hammer & chissel to peel it out.

Since the photo didn't show the upper part of the wall, he was wondering how you were going to install the shower valve since the PVC pipe was running between the existing hot & cold water pipes. Also why are the existing copper pipes running at an angle?

gmercoleza · #22 02-24-2007, 12:54 PM

Well I took a closer look last night, and the problem is a little more complicated, since the pipe actually goes right into the concrete (there is no bottom plate there).

Quote:

Originally Posted by Wodnek

They make something called a star drill. It is like a chisel but made for breaking up small areas of concrete without the dammage spreading. A 1/2 inch star drill should make it possible to expose just an inch of the pipe.

Sounds do-able, though I've never heard of a star drill. I have an air hammer with a chisel set, and will attempt to use that to clear an inch around the pipe.

Quote:

Originally Posted by Southern

I showed the picture to my son who is a plummer. His first comment was why don't you just break-up the concrete floor and do it the proper way? He does this all the time using a hammer & chissel to bust up the floor and use a bag of concrete mix to patch it up when done.

This really is a good suggestion. I'm going to get in there with the air hammer and chisel. Patching the concrete really isn't necessary since the area is not going to be exposed. I will be building a tasteful enclosure to cover it all up.

Quote:

Originally Posted by Southern

He said that you can peel back the existing PVC pipe but he recommends that after you cut the pipe, use a sawsall to cut a notch, heat it up with a torch and use a hammer & chissel to peel it out.

This is an even better suggestion. I will be trying this first before resorting to the hammer and chisel. My only issue is that the pipe may end up being jagged which might not provide a good sealing surface. But if it doesn't work out, I can always resort to chiseling the concrete.

Quote:

Originally Posted by Southern

Since the photo didn't show the upper part of the wall, he was wondering how you were going to install the shower valve since the PVC pipe was running between the existing hot & cold water pipes. Also why are the existing copper pipes running at an angle?

Not sure about the pipes running at an angle, all I can say is the builder didn't line things up properly. As for the shower valve, don't worry - the shower is not going on the wall at this exact point. After I put the T-fitting on, I will be running a 2-inch pipe about 3 feet away to the shower P-trap. The pipe will be turning left and running parallel with the wall.

Thanks for the suggestions - this gives me a few options. I still wish my fantasy coupler existed...

Brian Carlton · #23 02-24-2007, 01:07 PM

Quote:

Originally Posted by gmercoleza

This is an even better suggestion. I will be trying this first before resorting to the hammer and chisel. My only issue is that the pipe may end up being jagged which might not provide a good sealing surface. But if it doesn't work out, I can always resort to chiseling the concrete.

It will be jagged........for sure. Get out your 4" grinder with an 80 or 120 grit wheel and clean the top of it carefully. The grinder can move a lot of plastic in very short order so be careful............

mgburg · #24 02-24-2007, 01:48 PM

For the cleanup/prep work, I'd go with the Dremel (space considerations, doesn't look like you have too much to spare!), and use the PVC-Cleaner liberally, then dry-fit your whole system to be sure you're not, permanently, glueing in any "kinks" in your drainage system.

Then, finally, have a rubber mallet for the final glue/fitting. CAREFULLY drive your final fits together and fast. You don't want the glue setting everything too fast before it's "bottomed out!"

Good luck! I don't envy you on this project. But, when you're done, show us the pics!

cmac2012 · #25 02-24-2007, 02:06 PM

Quote:

Originally Posted by t walgamuth

you really don't want a lip inside your pipes. it will catch stuff and tend to plug up there. i still don't understand the problem. what are we looking at in the picture?

tom w

That's been my thinking on the male insert arrangement.

If the pipe is accessible from both sides -- in the photo looks like sheetrock on the back side as well, that could give you room to try to peel the elbow off using a dremel tool.

One of my favorite dremel bits is a carbide router bit looking thing, about 1/8 inch diameter, about $15 to $20. If you carefully cut vertical channels, about 1/2 inch apart, you might be able to peel that off. If not, having the other side of the wall open could hopefully give you enough room to chisel far enough down into the concrete to put on a normal female fitting.

I found a website, widgetsupply. com, that has great prices on diamond dremel bits. One or two of those might get you far enough down into the concrete w/o harming the existing PVC.

gmercoleza · #26 02-24-2007, 05:14 PM

Well I used some rotary rasps from Harbor Freight loaded into my drill and was able to mostly peel away the flange. Don't ask me why, but I did the stupidest thing and "chiseled" away at a seemingly loose piece of flange. Instead of the flange coming off, a small piece of pipe cracked off! Anyway, so I used a combination of sawzall and rotary rasp to remove everything down to the level of the flange (about flush with the concrete). Then I went on the other side, pulled the pedestal off the sink, and cut an access hole.

I took out my $3.99 air hammer set (once again from Harbor Freight) and went to town, carefully removing concrete from around the pipe. The air hammer chewed through the concrete like a hot knife through butter, and using several different chisels which came with the set, I was able to clear over 1 inch down.

Here's where it gets tricky - you guys tell me if I did everything OK. I squared and de-burred the edges of the pipe, then I blew out the dust and plastic shavings with the compressor. I cleaned out as much of the pebbles that I could; it was pretty clean. I did a dry fit, and everything was nice and tight, requiring some twisting and pushing to get everything to seat properly.

I washed my hands, took the damp paper towel, and carefully wiped the pipe down to remove dust. I took the purple primer and "scrubbed" the surface of the pipe and the inside of the T flange. I allowed it to dry about a minute, then swabbed PVC cement on the inner surface of the flange and about 3/4 inch down on the pipe stub (I didn't want to get too close to the concrete and swab grit up onto the joint area). Then I put the T on firmly while twisting back and forth. I lined everything up 90 degrees and then let it sit while applying pressure for about 30 seconds. Afterward, I let go.

Now when I let go, I heard - A SQUEAK! That indicated to me that there was plastic on plastic rubbing, or at least that is my thinking. So I wiggled the T fitting ever so slightly, and IT SQUEAKED AGAIN! I started to panic. I re-read the instructions on the PVC pipe and noticed that it said after putting a coat of cement on both parts to go back and PUT A SECOND COAT! I did not do this. However, I am confident that both surfaces were completely coated, with no dry spots. Did I not put enough on there? The instructions said not to put "too much" or else if it pooled it could weaken certain spots of the piping.

I pulled out a flashlight and my automotive dental-mirror-on-a-stick and inspected the joint from inside, and about 80% of the surfaces showed a damp, oozing condition. There were a few very small portions that did not show oozing, so I took a wire hanger with paper towel crimped onto the end, wet it with some cement, and lightly swabbed the apparently dry areas.

I wiggled the pipe again about 15 minutes later and it did not squeak. Here's my question: Was the squeaking actually from the 2 parts rubbing? I did not think it was possible, since the parts fit together tightly. Could it have been the pipe rubbing ever so slightly against the concrete?

I just don't want to cover it all up if it's going to leak.

Please keep in mind I am slightly OCD and tend to obsess over everything. I will think about this pipe while lying in bed at night, wondering if I did everything properly, even if I know I did.

Any thoughts?

Pics:

gmercoleza · #27 02-24-2007, 05:20 PM

It has been about 1/2 an hour since I glued everything. I just went back and wiggled slightly and heard no squeaking whatsoever. Should I be worried that it's not squeaking now?

Brian Carlton · #28 02-24-2007, 05:27 PM

Quote:

Originally Posted by gmercoleza

It has been about 1/2 an hour since I glued everything. I just went back and wiggled slightly and heard no squeaking whatsoever. Should I be worried that it's not squeaking now?

After 24 hours, go and try to pull that T off the pipe. It should be impossible to budge. If it's on there without movement, and you got glue all the way around one of the pieces, it won't leak.

Did the T go all the way down onto the pipe in the floor until it stopped on the inside shoulder...........or did the T hit the floor first?

gmercoleza · #29 02-24-2007, 05:57 PM

T bottomed out on the shoulder, did not hit the floor. There is about 1/2 inch extra before it could bottom out on the floor; I guess I got a little too ambitious with the air chisel. I guess better more than less...

I just wiggled the T again, and it is on there good. I have no doubt it is unremovable. I'm just worried there might be a pinhole area where water could seep out of on its way down to the sewer.

Maybe I am just overanalyzing...

I have a couple rags in there to block the sewer gases but will need to install the 2 elbows and at least connect it back up to the upper pipe, otherwise we can't use our bathroom tonight. I noticed the directions said it would be fully cured in 2 hours, so I will refit everything after that.

While taking a break, I fixed the 300E slipped window regulator arm - again. That little rubber piece just isn't holding the slider in the track anymore. So I put the window up and disconnected power to the regulator, then buttoned it all back up. Anybody know if that little rubber piece is available from MBZ?

gmercoleza · #30 02-24-2007, 05:59 PM

this project is going to run me about $600. I hope I get the value back when I sell. Even if I don't, this will make a nice third guest bathroom...