Originally Posted by MrMark52
Iím going to bet the gray is polybutylene which is what was used in stick and brick construction and RVís/motorhomes until sometime in the mod-late 90ís (out Ď91 coach had it, our Ď02 coach doesnít).
You may remember all the lawsuits that occurred when those systems started leaking.
A Sharkbite is a good solution to transition to todays PEX or male/female adapter that you can then use a reinforced hose to make the connection to the toilet valve.
But you have to make sure to buy the PEX adapter that is compatible with polybutylene! And, you have to use the ferrule-like tube insert to support the poly to insure it wonít collapse against the o-ring pressure of the Sharkbite.
The poly isnít that hard to cut with regular pvc pipe snips.
Just be sure to check any/all original fittings that you might disturb when doing the work.
The lawsuits that ensued as a result of the leaks was not due to poly failure, but leaks that occurred at the fitting joints.
Out Ď91 coach that we got in Ď18 likely had a hard to get at joint leak from its first use. By the time I figured out what was leaking, most of that area of the floor had rotted out. Fortunately most of that area was under the bathroom cabinet and water heater. But it did create a squishy walk into the bathroom after 2-3 days of water hook-up use until I finally found the leak.
Totally rebuilt 1/2 of the coaches water system when I figured it out.
The gray polybutylene which was used in stick and brick construction and RVís/motorhomes until sometime in the mod-late 90ís because it failed and will fail. Large law suits to re-plumb houses do to the failures became class action back then. The stuff was junk. Now this involved higher pressures than most RV's see and the crimp connectors for them failed as well as pipe splitting. Only use blue for cold and red for hot.
From an article about selling homes with polybutylene pipes:
Why Is Polybutylene Bad?
Polybutylene pipes were first produced in the mid-1970s. They seemed to be a perfect material for plumbing pipes because they were inexpensive and held up well under high water pressures.
By the 1990s, however, problems had begun to surface. Minerals in the water, particularly chlorine that was used for purification reacted poorly with the pipes. This caused the pipes to deteriorate and become brittle on the inside.
When temperatures rise and fall, poly pipes will expand and contract. When this happens, weakened pipes will rupture.
Polybutylene water supply pipes broke in the ground outside homes causing soil erosion and foundation damage (if this has already happened to your property, here is an article about selling a house with foundation problems
). Interior pipes ruptured inside the walls. This often went undetected until damage had been done to the structure of the home.
A frequent by-product of the water damage was mold. Mold can cause respiratory problems in adults and the development of asthma in children.