Fresh tank manufacturing flaw :(

Brantel · 04-17-2021, 09:28 AM

So I have a leak on my fresh water tank. It only leaks when the tank is completely full. I chased it down and it appears that the fitting that is glued to the tank at the top where the vent line attaches did not get glued all the way around. Now I need to know what kind of glue/solvent to use to try and seal this leak. It would be covered under warranty but that will take weeks to months at the dealer. Not sure if they would try to fix it or just replace the entire tank.

The area in the red circle on the attached pic is where the leak is. I can stick my fingernail between the flange of the fitting and the tank.

Anyone know what solvent/glue/sealant will work on these tanks?

**chuckster57** · 04-17-2021, 09:34 AM

Those fittings are "spin welded" meaning there is a machine that spins the part and they melt together. Since there isnt any pressure on that fitting I would use any FOOD GRADE sealant.

Brantel · 04-17-2021, 09:56 AM

Quote:

Originally Posted by chuckster57

Those fittings are "spin welded" meaning there is a machine that spins the part and they melt together. Since there isnt any pressure on that fitting I would use any FOOD GRADE sealant.

That's what I thought as well but there is clearly some sort of adhesive being used to bond these fittings to this tank. You can see where it oozed out around them.

**chuckster57** · 04-17-2021, 10:04 AM

Are you sure it isnt the same material as the tank? Permatex makes a tank repair kit and it doesnt say NOT to use on a fresh tank.

**flybouy** · 04-17-2021, 10:07 AM

As CFhuck stated they are "spin weld" fittings. They are chucked into a drill and spun at hight speed so I think what you are looking at is the result of the plastic being slung out by centrifical force, like a polisher slings wax around a buffing pad.

Brantel · 04-17-2021, 10:19 AM

Quote:

Originally Posted by chuckster57

Are you sure it isnt the same material as the tank? Permatex makes a tank repair kit and it doesnt say NOT to use on a fresh tank.

Quote:

Originally Posted by flybouy

As CFhuck stated they are "spin weld" fittings. They are chucked into a drill and spun at hight speed so I think what you are looking at is the result of the plastic being slung out by centrifical force, like a polisher slings wax around a buffing pad.

I hear what you are saying but what I see does not agree with you. I have seen many spin welded fittings and these do not look to be spin welded. Spin welded would also not likely have a failure like this one.

**chuckster57** · 04-17-2021, 10:26 AM

Ive taken a closer look WITH MY GLASSES ON, and I still say its a failed spin weld. get the permatex kit and call it a day

notanlines · 04-17-2021, 11:16 AM

As a fairly sharp RV tech once said, "Get the Permatex kit and call it a day." I concur 100%. There is zero pressure so it is almost can't miss.

**JRTJH** · 04-17-2021, 11:42 AM

Or, get a pencil type soldering iron and "finish the spin weld seal"... If you "really, REALLY want to get fancy" you can get a "plastic welding kit" from Harbor Freight and spend 3 or 4 days "perfecting your bead"....

For me, since it's not something every visitor is going to be checking, I'd probably not even wipe off the soldering iron tip. Who cares if there's a little "no lead solder" to contaminate the melted plastic.....

bobbecky · 04-17-2021, 12:01 PM

This product might work. https://www.permatex.com/products/sp...nk-repair-kit/

**chuckster57** · 04-17-2021, 12:09 PM

Quote:

Originally Posted by bobbecky

This product might work. https://www.permatex.com/products/sp...nk-repair-kit/

I believe thats the one I said to use. Thank you for posting the link..I'm buried in the garage under my 4th car for the day..

Brantel · 04-17-2021, 02:24 PM

So I tried the soldering iron trick mentioned above and it did a pretty good job. Fixed the major leak. There is still a pinhole up on top somewhere. It is very difficult to work in the area of these fittings without 6 arms. I need one for holding a mirror, one for holding the flashlight, one for holding the wires out of the way and one to run the soldering iron. LOL.

Whoever built this tank was not having a good day.

Another issue is that Keystone uses a spiral wound reinforced hose for the fill line. It is almost impossible to tighten a clamp enough to seal this hose due to the spiral path water has to leak out of. Not a good application for that kind of hose.