Replaced kitchen sink drain pipes, still slightly leaking

Hello! So my kitchen sink pvc pipes started leaking at one of the joints. When I looked at it closer, I found that the piping was done incorrectly. So I went and redid all the piping. Everything seemed ok at first, but since I have been monitoring it, there is a slight leak where the pvc pipe connects to the metal drain. I tightened it as much as I could without the metal drain rotating. That brings me to my first question... I was told if the metal drain can rotate, that means it’s not on tight enough. I tightened it as much as I could, but it still seems to want to rotate. I tightened it with a wrench and my bare hand holding the base in place, but it still wanted to rotate. Is there something else I need to do to make it tighter?

Then to my second question. How do I stop the leak? All the piping is brand new. I did not put any sealant or washers or anything to seal that joint... do I need to? It’s possible I put a washer on there as I put one on all the other joints, but I don’t remember putting one on there and don’t want to take it all apart unless I am suppose to have one there.

Post a picture of the set up

A picture would be helpful. What is the "metal drain"? If possible, I prefer to use all PVC from the bottom of the sink all the way to the stack. Metal traps rot out, PVC traps don't.

jeffmattero76 said:

A picture would be helpful. What is the "metal drain"? If possible, I prefer to use all PVC from the bottom of the sink all the way to the stack. Metal traps rot out, PVC traps don't.

Click to expand...

Thank you both for your responses. I can post a picture of how it used to look to give a better understanding and when I get home I can take a pic of the final product. Sorry if my terminology is not correct... I am just starting to learn about plumbing and how it all works, so bear with me ��. By metal drain I mean the metal piece that goes into the sink. You can put a stopper in it to catch food and other things and also use the stopper to clog the drain so the basin can fill up with water. I put the “plumbing plaster” (forgot the name, but used the right product) stuff between it and the sink basin to seal it. The “metal piece” I speak of can be seen at the top of the picture I took. Again, this was the pic of it done incorrectly. You can see in the picture that the p-trap was on backwards as a jimmy rigged approach to solve the issue that the sewer drain was higher than the sink drain. This caused the water to drain slowly due to physics. I put the p-trap on correctly and rerouted it to the sewer pipe to the left in the picture instead of the one to the right like it was previously done. That sewage pipe is lower, so I can get a faster drain.

redhawk87 said:

Thank you both for your responses. I can post a picture of how it used to look to give a better understanding and when I get home I can take a pic of the final product. Sorry if my terminology is not correct... I am just starting to learn about plumbing and how it all works, so bear with me ��. By metal drain I mean the metal piece that goes into the sink. You can put a stopper in it to catch food and other things and also use the stopper to clog the drain so the basin can fill up with water. I put the “plumbing plaster” (forgot the name, but used the right product) stuff between it and the sink basin to seal it. The “metal piece” I speak of can be seen at the top of the picture I took. Again, this was the pic of it done incorrectly. You can see in the picture that the p-trap was on backwards as a jimmy rigged approach to solve the issue that the sewer drain was higher than the sink drain. This caused the water to drain slowly due to physics. I put the p-trap on correctly and rerouted it to the sewer pipe to the left in the picture instead of the one to the right like it was previously done. That sewage pipe is lower, so I can get a faster drain.

Click to expand...

Ok, now I understand. What you are calling the "metal drain" is called the strainer. What you are calling "plumbing plaster" is called plumbers putty.

You need to determine where the leak is coming from. My guess is that you have not tightened the strainer tight enough. They make a special tool to hold the strainer so it doesn't spin when you tighten the METAL nut on the bottom of the strainer. This tool looks similar to the chess piece known as a "rook". Don't go out and buy that tool if you don't have it. Instead, put the handles of a pair of pliers or channel locks into the holes on the strainer. Then get a second person to help you. Insert a screwdriver between the handles of the pliers to act like a handle and prevent the strainer from spinning as you tighten the METAL nut. As you do that, putty will likely squeeze out from under the lip of the strainer. Don't go crazy, but that nut should be firmly tightened.

If that doesn't stop the leak, the other possibility is the plastic washer between the tailpiece (the first plastic pipe below the strainer) and the strainer. That should be a tailpiece washer (cross section shaped like an upside down L) rather than a beveled washer. Still using the pliers to hold the strainer from spinning, tighten the PLASTIC nut that holds the tailpiece to the strainer.

To test for leaks after each step, use a dry towel to dry all of the pipes, fill the sink up with water and then pull the plug to flood the pipe.

Let us know how you make out.

redhawk87 said:

Thank you both for your responses. I can post a picture of how it used to look to give a better understanding and when I get home I can take a pic of the final product. Sorry if my terminology is not correct... I am just starting to learn about plumbing and how it all works, so bear with me ��. By metal drain I mean the metal piece that goes into the sink. You can put a stopper in it to catch food and other things and also use the stopper to clog the drain so the basin can fill up with water. I put the “plumbing plaster” (forgot the name, but used the right product) stuff between it and the sink basin to seal it. The “metal piece” I speak of can be seen at the top of the picture I took. Again, this was the pic of it done incorrectly. You can see in the picture that the p-trap was on backwards as a jimmy rigged approach to solve the issue that the sewer drain was higher than the sink drain. This caused the water to drain slowly due to physics. I put the p-trap on correctly and rerouted it to the sewer pipe to the left in the picture instead of the one to the right like it was previously done. That sewage pipe is lower, so I can get a faster drain.

Click to expand...

Also, I just noticed that the way you are holding that trap is backwards. The long leg of the J should go on the tailpiece.

jeffmattero76 said:

Also, I just noticed that the way you are holding that trap is backwards. The long leg of the J should go on the tailpiece.

Click to expand...

Yeah, as I said in my post, that is a picture of how it used to be before I fixed it. I can post an updated picture when I get home of the final product if it helps. I am already aware of where the leak is. It is between the strainer and the tail piece. But, I was having trouble tightening the strainer with the sink basin and also tightening the strainer with the tail piece without the strainer rotating. I will try with the pliers and screw driver! Then hopefully I can remove the tail pipe. The washer you are describing doesn’t ring a bell so I probably forgot to put it on and probably why it is leaking! Thanks for your help! I will definitely try that tonight and update you.

Turns out I never bought the tailpiece washer and hence why I never put one in. I bought one and put it in and so far that seems to have fixed it! Thanks for the help. The below pic is the (almost) final product. Still need to cut off the higher sewage pipe that is not capped and cap it as I am no longer using it.

redhawk87 said:

Turns out I never bought the tailpiece washer and hence why I never put one in. I bought one and put it in and so far that seems to have fixed it! Thanks for the help. The below pic is the (almost) final product. Still need to cut off the higher sewage pipe that is not capped and cap it as I am no longer using it.

Click to expand...

Looks good. Glad to hear the tailpiece washer seems to have solved it.

For the horizontal unused pipe, you could cut it nearv the middle, glue on a female threaded adapter and then screw in a cap. That would allow you to use it as a clean out if needed.