Leak at P-trap sink connection

[Grendel]

OK I just finished installing a new garbage disposer. I did not remove the P-trap. Anyway maybe it was there before, maybe not but there is a leak around the chrome nut that connects the P-trap to the pipe coming out of the wall. Every other fitting there is no leak and it's fine. The problem is I can't get the P-trap nut tight or loose. It won't budge. I'm scared to give it anymore force than I already am because I don't want to hurt the PVC pipes. It appears to me that under the chrome connection there is some brown stuff on the threads. Not sure, just a guess. I and no one else has messed with it that I know of but I am not the original owner. Is it plumber time? What is causing the leak?

[David Martel]

Grendel,

It's possible that the brown stuff is rust from years of slow leak or it could be thread cement. You could try a penetrating oil like WD40. If you have good access to the pipes have an assistant hold both pipes while you try to turn the nut. You can try to cut the nut off with a hacksaw or chisel. But the easiest fix is to dry the connection well and apply some sort of caulk. Don't use the sink for a day while the caulk dries. This is a low pressure connection so caulking will work well here.

Good luck, Dave M.

[Grendel]

Isn't the caulk sorta getting around the problem? Isn't there maybe a gasket or something that is bad in there and when replaced the diposer it caused enough movement to upset it? Some guy at Home Depot said there's no gasket at that type of connection. If there isn't then what causes the leak?

The connection is never dry now. The trap always has water in it so it will always leak. I guess maybe it would eventually go down enough if I didn't use the water.

[Des Perado]

Listening to the "guy" at Home Depot can be the source of many problems. Best to pay a visit to a real plumbing supply store - not a hardware store - but a store that just sells plumbing supplies. You will get your best information there. Des

[David Martel]

Grendel,

Perhaps I'm confused about your problem. I thought you had a leak where the stub out pipe and the trap were joined. I think that only the trap contains water. The pipes on the sink side and the stub out side should drain and should not hold water. If what I've just described is your problem then let the joint dry for a day (don't use the sink). It should be bone dry if no one uses the sink. Caulk the joint and let the caulk dry for a day. Spread some newspaper under the joint and begin using the joint. Look for drips.

Dave M.

[Grendel]

You are correct I have a leak there where the pipe coming out of the wall an P-trap connect. The first chrome fitting after the wall.