Bathroom sink drain leaks 2014.5 AI

[Air99]

There was a small pool of water formed under the coach on our last camping trip, located right below the bathroom sink (in front of the right rear wheels), upon inspection when I got home revealed that the plastic threaded collar connecting the sink drain to the HEPVO valve below has stress fractures and is leaking when tested. I am a landlord with 30 years of plumbing repair under my belt but the Interstate setup left me scratching my head!
If you are familiar with a kitchen sink P trap arrangement whereas the use of slip joints and beveled seal rings along with threaded collars make for easy water tight connections between dissimilar pipe size and distance, well none of them were used here!
What it had was a stiff pulling together of hard section of PVC piping being glued together along with the vent pipe to the roof using only the threaded collar mentioned above, not to mention the whole assembly was misaligned by a good 1/8" to the drain mating surface and they compensated by using huge amount plumber putty oozing out of every joints, added to this stressed fittings the rigors of the road it's a matter of when and not if it shall fail.
I was able to fix it with leftover part bin from my garage, sawing off a piece of plastic kitchen P trap that has the same thread and beveled end lip to screw into the HEPVO valve below and just plain end pipe on top so a rubber joint (Lowes or home depot) and hose clamps can slip over it and the drain to provide both a water tight AND a flexible connection. I swear by these super handy rubber joints they even make them in P trap configuration to deal with leaks due to vibrations from under sink food disposers. Make sure to use plenty of teflon tape on the threaded sink drain pipe before slipping on the rubber. See attached pics of the cracked collar and the fix.

[Top69dog]

What can I say, AI really did a poor job putting things together for the price they charge, I pray mine holds up for few more years

[Air99]

Originally Posted by LateNight

You are not alone in your misery! I found the same threaded collar broken on my 2016 Interstate GT twin a few weeks ago. Same deal with the broken piece being used to pull the pipes together. They had the HEPVO valve tightened so that the offset was going the wrong way. Green sealer everywhere. The sealer had dripped into the HEPVO valve about two inches but stopped short of the part that closes to prevent back flow.


I am amazed there are not more people with this issue, really poor design/construction. Nothing should ever be put together with an ABS collar like that under stress, they are brittle and break too easy.


I am not sure I am following the sequence of your replacement parts...Starting at the sink drain:
-Standard 1 1/2" threaded to female PVC fitting
-Rubber splice with clamps (2" to fit around the OD of the PVC fitting reduced to 1 1/2")
-1 1/2" section of an old p-trap with the threads that would normally have a nut on them screwed into the top of the HEPVO valve


I am not sure I have enough length to fit this solution into mine but I will give it a try if I have the correct details above.


The fitting that is broken is an uncommon fitting that the big box stores and plumbing wholesaler I called have never seen.


I wonder how many people have this issue and don't realize it. If they don't use the sink much it would just keep leaking and rotting out the floor. I know mine must have been broken for at least a while because I found pink antifreeze residue on it.


Thanks,
Dave

Sequence goes like this from sink:
- wrapping plenty of teflon tape onto the threaded metal end of sink drain pipe to prepare it for the rubber boot.
- measure and cut the upper end of a commonly found J-shaped part of a sink P trap, I will put a picture of it on the forum app.
- Slip the smaller end of rubber boot onto this piece and turn it upside down to attach to the hepvo valve's threaded collar, there's enough give to the piping assembly that you can pull on it to line up the parts, it fits perfectly onto the beveled end inside hepvo valve.
- Slip the larger end of rubber boot up onto the sink end mentioned in step 1. The beauty of the rubber boot here is it makes it possible to even assemble the connection, nothing else will fit between the 2" space given!
- strap on the hose clamps, tighten them and you are done.

You are very welcome and good luck!

[Air99]

[Air99]

Originally Posted by Top69dog

What can I say, AI really did a poor job putting things together for the price they charge, I pray mine holds up for few more years

There appeared to be a small drain hole on the metal floor of my rig to allow the leaked water to drain out, if it's plugged you may not see any leaks from outside vehicle.

[Air99]

Originally Posted by Top69dog

What can I say, AI really did a poor job putting things together for the price they charge, I pray mine holds up for few more years

We're suckers for the beautiful interior decor and cabinetry!

[TG Twinkie]

It's not just the shiny units.
I own an Argosy, but I also own a new SOB. In the SOB the galley sink drain sprung a leak. Both sink basket nuts were only hand tight. PLUS there is 7' of unsupported 1 1/2" ABS drain pipe hanging from the slip joint of the "P" trap. Need I say more.
A piece of plumbers tape 5" long and 2 screws solved the problem.
My 43 year old Argosy has never given me problems like this. There is a caveat. I installed all of the fresh water and DWV piping new 8 years ago.
It is too bad that people have to deal with this stuff.
I consider myself one of those lucky soles who has the knowledge and skills to resolve these issues. And not have to pay $100/hour or more for someone to fix it. The $100 an hour doesn't guarantee the quality of the job done.
At least when I do it and something goes wrong. I know where to find the guy who did it. And he doesn't charge much.

[Air99]

Agreed. I waited until retirement to buy the thing so I can repair it full time! ;-)

[VAtom]

Originally Posted by Air99

What it had was a stiff pulling together of hard section of PVC piping being glued together along with the vent pipe to the roof using only the threaded collar mentioned above

This has happened to quite a few people, including me.

Attached is a photo from Joe RV Guy with a similar problem. The "collar" is a swivel union and there is zero clearance to put in new parts or slip joints.

My fix is probably not permanent so I appreciate your solution, description and photo.

[Air99]

Thanks for the comment. All they really need is a flexible accordion like coupler between the sink and the hepvo valve which should be mounted a couple inches lower, saving us owners a bunch of headaches!

[Delores]

Thought that my buying new or almost new, I would be spared years of repair work. Only 15,000 miles but 3rd owner so no warranty for me. I’m not about to tingle with anything so I’ll have to bite the bullet and take to repair shop. Thanks all for support. This info helps when we do take it in.