ABS compression joint leaking

[Stan in Oly, WA]

I had to change the strainer in my kitchen double sink. When I finsihed I had a leak in the ABS compression fitting on the side of the trap away from the tailpiece. That tightened up okay and stopped leaking, but when I ran water in the other sink---the disposer side---the compression fitting on one side of that trap leaked. No fair! I hadn't disconnected that side. (But I definitely had bumped it a few times.)

I'm always surprises me when ABS to ABS, or ABS to nylon (or whatever those white gaskets are) compression fittings don't leak, or when they do leak but tightening makes the leak stop. When tightening doesn't make the leak stop, is there something else that will? Plumber's putty in the joint? These ABS traps are not constructed to take replacement gaskets or slip rings. When they can't be tightened enough to stop a leak, it looks like you have to cut them out of the system and replace them. I really don't want to have to do that.

Thanks, Stan

 

[2t2@IA]

I have used silicone caulk. The joint should be dry,and the silicone should set at least 12 hours, and 24 is better. One time I put a gear hose clemp over the silicone. It is still holding.

 

[Stan in Oly, WA]

Hi 2t2@ia,

Can you take a joint apart after it has been silicon caulked? I want to make it stop leaking but I also want to be able to take the traps apart when necessary. I used to do sink drains using totally glued together ABS. It was great for not leaking, terrible for getting a snake in to clear a clog, or trying to get out something that had fallen down the drain.

All the best, Stan

 

[Dusty MI]

I'd use some pipe dope, just brush a thin coat. It's surprising what a little of it will do.

Dusty

 

[thurlow]

Just went thru something similar; doing a minor kitchen remodeling........replacing dishwasher and sink. New sink is about 9 inches deep; different size tubs; tall,'goose-neck' faucet. Old drain was a combination of metal and PVC (or whatever the 'plastic' stuff is). None of the old would fit, so I bought all new PVC; put it together and I've got a slow leak at one of the compression fittings. Tighten it up a little; no change; tighten it up some more; no help. Took it apart and looked at white/nylon(?) slip ring. No nicks, no burrs, it looked perfect. Put a new one in that looked just like the old one; problem solved. Couldn't figure out what was different...........

 

[Stan in Oly, WA]

Thanks, Dusty. I'll give it a try.

All the best, Stan

 

[Stan in Oly, WA]

Hi thurlow,

That's been my experience, too. The trouble with the ABS P-traps you buy is that they are made so that at least one joint cannot be made leak-proof by replacing compression parts. The joint on the opposite side of the trap (lowest bend) from the sink drain tailpiece is cast with tapered mating pieces. This makes it an ABS to ABS compression connection which either tightens enough to prevent leaking or, as in my situation, doesn't. If there isn't a way to add something to seal the joint (pipe dope, plumbers' putty, silicon caulk, etc.) you may have no choice but to cut the assembly out and replace it. This isn't a problem on the tailpiece side, but on the downstream side of the trap you don't always have a straight run of pipe that you can cut and reconnect to. This means that you might have to cut back a considerable part of your drain assembly to get to a place you can reconnect. If there's a way to make a reliable glued connection somewhere other than a place where you have at least a 3/4" length of straight pipe, I don't know what it is.

All the best, Stan

 

[KF]

I have found that the ABS to ABS fittings need perfect alignment and need to be tightened first to get the alignment needed to seal. The joints with the plastic insert seal are a little more forgiving, but still require fairly close alignment. Without close alignment and being tightened down as such, the seal will take a set and if taken apart the seal would have to placed in the exact previous loaction in order to have a chance to seal. That is why using a new seal often works as it is not distorted.

 

[Bob S.]

Howdy
I always use silicone caulk on the joints ( yes it will come apart later, no problem), the reason I always use the silicone is, the first time someone dumps boiling water down the drain everything starts to loosen up and its just a matter of time before the leaks start.
Bob S.

 

[bc]

Stan, I've used pipe dope and even teflon tape around the threads and the slip ring. What a lousy invention. They have to be able to withstand pulling the plug on a full sink. I think I like the silicon caulk idea better though with a bead on the slip ring and the threads.

Where are you finding abs fittings? Anything over 15 years old seems to use black abs pipe and fittings for drain work. About all you see new now is white pvc fittings and tail pieces at the stores. Makes it kind of a burger to have to use the combo abs/pvc glue and then hope it holds.

 

[2t2@IA]

Depends on how it's done. The way I've worked is to just put some silicone on the outside of the leak, kind of like a patch. While I have never done it, I think you could take a razor blade and slice it off and get it apart. Hope this helps.

 

[Old Timer in Ohio]

Hey there:
If you look closely at some of the tubes, you
can see a "joint line" where the mold thats
used to make the "pipe" comes together.
Just carefully scrape the "joint line" smooth,
it's worked for me MANY MANY times!!!
Bob
God Bless