Swivel Fitting Gasket issues

[swmurray]

Hi: I've been chasing leaks in my '20 310GK-R and have now noted some "new" leaks at the NPT swivel fittings at the Nautilus manifold system. So wondering if there are guidelines for use of these swivel fittings.
I haven't found much info on these fittings on the web or this forum. Maybe I'm not searching correctly.

Thank you!



Background: We normally have city water but have been on pump for the last two months due to a water system failure at this site. We have also used the pump to siphon water from 5 gallon jugs to refill the system as needed. I noted the pump cycling on occasionally when we were not using water, but found no leaks initially. I talked myself into temperature swings in the system being the cause. As time went on the pump cycling got worse and found a leak at the plastic check valve at the HWH outlet.

The check valve body had cracked just inside the heater nipple as if it had been stressed from overheating and/or over tightening on initial installation. Had to carefully cut and pry out the pieces. Replaced with a brass nipple as a temporary substitute and decided to change out the inlet (cold) side which had a nylon fitting and the teflon tape installation looked horrid.

I reconnected the swivel fittings and both leaked!. I reset and tightened to my max my comfort level (for plastic but they both still leaked. The hot (red) side fitting appeared to be leading at the vinyl hose (clamped) side and the cold (blue) side was leaking at the swivel joint.
So back to the store (2 hr RT) to get these fittings. They had brass fittings, and yes, it is a PEX fitting on a vinyl hose the way GD does it (not my favorite). New swivel fittings seemed to work, but now we find a small seepage at two swivel fittings on the Nautilus manifold. These are small, but before I go further I'd like to step back and make sure I'm not missing something about these swivel fittings. One of the leaking fittings at the Nautilus was at a fitting I took off to repair the cold (blue) side at the HWH. So just disconnecting and reconnecting might have done something. But the other leak is on a fitting that hasn't been disturbed (by me).
DW looked too and we agree the leak appears to be at the swivel joint.

Attached is a photo of the two swivel adapters replaced after leaking at the HWH. Note the internal gaskets. The blue side gasket is clearly distorted and has at least two different seat depression patterns. The red side gasket has scoring on the surface. I had tightened both carefully using a wrench and could not stop the drip.

So I am trying to understand the basic items to check/do when working with these swivel fittings.
Where is the mating surface? I presume the gasket and the internal tube of the swivel fitting sits inside the NPT mating nipple so both need to be round, de-burred and smooth. Is this correct?
Is the mating surface different when using a brass NPT fitting from the plastic/nylon fittings or valve connections?
Should I always plan on replacing these fitting when changing out the mating NPT side?
How tight should these fittings be pulled up. I thought it was finger tight and no more than a turn or so with a wrench but careful not to over tighten past the gasket compression point.

Thank you!

[DECelt]

Hi: I've been chasing leaks in my '20 310GK-R and have now noted some "new" leaks at the NPT swivel fittings at the Nautilus manifold system. So wondering if there are guidelines for use of these swivel fittings.
I haven't found much info on these fittings on the web or this forum. Maybe I'm not searching correctly.

Thank you!



Background: We normally have city water but have been on pump for the last two months due to a water system failure at this site. We have also used the pump to siphon water from 5 gallon jugs to refill the system as needed. I noted the pump cycling on occasionally when we were not using water, but found no leaks initially. I talked myself into temperature swings in the system being the cause. As time went on the pump cycling got worse and found a leak at the plastic check valve at the HWH outlet.

The check valve body had cracked just inside the heater nipple as if it had been stressed from overheating and/or over tightening on initial installation. Had to carefully cut and pry out the pieces. Replaced with a brass nipple as a temporary substitute and decided to change out the inlet (cold) side which had a nylon fitting and the teflon tape installation looked horrid.

I reconnected the swivel fittings and both leaked!. I reset and tightened to my max my comfort level (for plastic but they both still leaked. The hot (red) side fitting appeared to be leading at the vinyl hose (clamped) side and the cold (blue) side was leaking at the swivel joint.
So back to the store (2 hr RT) to get these fittings. They had brass fittings, and yes, it is a PEX fitting on a vinyl hose the way GD does it (not my favorite). New swivel fittings seemed to work, but now we find a small seepage at two swivel fittings on the Nautilus manifold. These are small, but before I go further I'd like to step back and make sure I'm not missing something about these swivel fittings. One of the leaking fittings at the Nautilus was at a fitting I took off to repair the cold (blue) side at the HWH. So just disconnecting and reconnecting might have done something. But the other leak is on a fitting that hasn't been disturbed (by me).
DW looked too and we agree the leak appears to be at the swivel joint.

Attached is a photo of the two swivel adapters replaced after leaking at the HWH. Note the internal gaskets. The blue side gasket is clearly distorted and has at least two different seat depression patterns. The red side gasket has scoring on the surface. I had tightened both carefully using a wrench and could not stop the drip.

So I am trying to understand the basic items to check/do when working with these swivel fittings.
Where is the mating surface? I presume the gasket and the internal tube of the swivel fitting sits inside the NPT mating nipple so both need to be round, de-burred and smooth. Is this correct?
Is the mating surface different when using a brass NPT fitting from the plastic/nylon fittings or valve connections?
Should I always plan on replacing these fitting when changing out the mating NPT side?
How tight should these fittings be pulled up. I thought it was finger tight and no more than a turn or so with a wrench but careful not to over tighten past the gasket compression point.

Thank you!

I haven't gotten as far as you, but already had one leak at the back of the Nautilus panel from a really cheesy swivel fitting that had too much downward pressure on the right angle.I am waiting for a pex tool from Amazon to get into things. I plan on using a combination of shark bite swivel fittings and PEX crimp fittings...

I also bought some brass fittings and have the same question as you!

I have a basement watchdog leak detector installed in the basement. It's already paid for itself[emoji1]

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[Parkerga]

I'm having the same problem, have two leaking fittings on the back of the Nautilus panel of my 2020 310-GK. I went to my RV dealer and bought new silicon gaskets (like the ones in the photo above). Replaced them and now they leak worse that the old seals! I was hoping to find something on this site that would help me but I see no one replied to this thread. Is there a solution to this? Are the seals in the brass fittings you mentioned above different? Also, these are not NPT fittings, since they are straight thread not tapered like NPT. I haven't seen fittings like these before, but I know I don't like them.

[Jerryr]

Read this 3 year old posting. https://www.mygrandrv.com/forum/show...146#post167146

Possible 1/2” Cone washer source.

https://parts.unitedrv.com/products/...nt=Catch%20All

Jerry

[FT4NOW]

In my opinion, the best solution for longevity is to get rid of the Nautilus system and replace all flexible hose with PEX. I did this on my Momentum and never had any problems after that. As an additional bonus, since I used real ball valves made of metal that dont use orings, I could operate the valves without having to depressurize the system each time. Operate the Nautilus system while it is still pressurized and hope you dont blow out an oring. Nautilus uses so many fittings that if one leaks, you need to remove numerous ones to fix it and then hope you didnt make a new leak.

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[Jerryr]

Looks like these might be a good brass vs plastic replacement https://www.amazon.com/XFITTING-PEX-...dp/B07FX6KWPS/

Or these https://www.amazon.com/SharkBite-UC5...dp/B00A8HSWIC/

[Parkerga]

Thanks for the info. These are the washers i bought and didn't fix the problem. I replaced the fitting with a shark bite brass fitting with integral seal and it still leaks badly. I'm beginning to wonder if it's the ball valve fitting that's the problem.

[Parkerga]

Thanks for the advice. Did you use the Nautilus panel and replace all the ball valves? Or did you throw out the panel and make your own? Also, who's ball valves did you use? Sounds like my only option since the brass shark bite I tried leaked as well. Thinking it may be the ball valve. Thanks, Glenn

[FT4NOW]

Thanks for the advice. Did you use the Nautilus panel and replace all the ball valves? Or did you throw out the panel and make your own? Also, who's ball valves did you use? Sounds like my only option since the brass shark bite I tried leaked as well. Thinking it may be the ball valve. Thanks, Glenn

I assume you are replying to me. Best to use reply with quote to minimize confusion. If you search the forum for 'Good bye Nautilus' you can see the topic I started and it includes pictures.

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[geotex1]

First, those are NPSM fittings and they are being used in an improper mating, which is unfortunately status quo in the RV world. They'll work, but it destroys the cone seal. Contrary to what you might expect, the cone seals from brand to brand are not interchangeable. Moreover, the fittings you have are NSPM to PEX, which has a different inside diameter than the vinyl tube. Most of us ultimately get rid of the vinyl tubing, but if you are not prepared to do this, you can get an NSPM to hose barb to get to a leak-free state. Very hard to find in a 90, but straights are common.