Sunday, January 29, 2023


Should we replace the water supply hose going to toilet?

Dear Dave,
There was a nick in the flexible water line with white sleeve inside. We have repaired it with a connector and two clamps. No leaks. However, there is now a small amount of water visible between the inner liner and hose. Will this eventually become a problem? Do we need to replace entire water supply line? Thanks. —Ron, 2018 28 ft. Minnie Plus 5th wheel

Dear Ron,
[It took a couple of back-and-forth emails to nail down what hose was having the issue and Ron finally sent this photo. Ron identified it as the supply line going to the toilet.]

This is a ½” braided plumbing line that is pretty common in the RV industry and even some residential applications. This type of hose is sold at most home improvement stores. You can also get it at Amazon here. It is not a two-part hose; rather, it is a construction that has braiding incorporated into the material. So if there is water between what looks like an inner and outer hose, the material has separated.

If there is a separation, I would suggest replacing the entire hose, as it has created a weak point that typically will keep “creeping” and separating away from that area. Here is what the hose looks like.

Location of the water supply hose

What also concerns me is how the hose is just hanging in the compartment. Typically, RV manufacturers would use a more rigid PEX supply line going to the bathroom and then this type of more flexible hose going to the toilet valve. The ½” braided hose could not be supported well enough in this compartment and will move far too much while traveling down the road. In my opinion, that may be what caused the nick in the first place. In the photo you can see red and blue PEX lines running on the other side of the compartment.

Also, since this is a 2018, this might be a DIY project rather than original equipment. I would replace the entire line with a PEX supply line and crimp connector, which you used in the connection.

There are some handy compression fittings. However, with the bouncing you will experience going down the road and the placement of this line hanging from the top, I would use the crimp connectors since you already have the crimper. If not, you can get one at Amazon here.

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1 month ago

Hi Dave. As I look at the picture you’ll see a tie wrap on the right that’s meant to be held in position as it has an eyelet for a screw. I also noticed a hole just above on a support beam & it looks like the hose was supposed to be secured there! Maybe it was never secured or Ron had taken it out so he could work on it!

1 month ago

Your diagram of the hose is confusing. 1/2 inch ID plus 1/8 inch wall thickness equals 5/8 inch, but your diagram shows 3/4 inch OD. What happened to the other 1/8 inch?

1 month ago
Reply to  Linda

Well it does say 1/8″ wall & thats 1/8′ X 2 = 1/4′ + 1/2″ = 3/4″. May sound weird but that the way they call out any type of tubing! Do it in reverse 3/4″ O.D. & 1/2″ I. D. subtract them & get 1/4″ now divide it by 2 & get 1/8″ wall, as there is a wall on each side! Yup I’m sure someone will have a better description.

1 month ago
Reply to  Snoopy

Exactly. There are two sides to everything.

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