Dealing with existing polypropylene tubing

[Jammer]

New to me boat with some freshwater plumbing problems. The existing tubing appears to be polypropylene. The boat was built in 1999 which was after polybutylene pipe was discontinued but before PEX was widely available, so that makes sense. The tubing is terminated with compression fittings, like the one in the photo, that use a stainless steel "grabber" ring together with a rubber cone washer. In a few cases, polybutylene (Qest) fittings have been retrofitted.


I have a number of plumbing repairs to complete. I have to repipe the connections to the water pump, add a bypass to the water heater, and replace some fixtures. The fittings are deteriorated with the rubber washers not remaining supple enough to reuse reliably. I will be replacing portions of the plumbing with PEX as I go but do not wish to replace every water line on the boat at this point.


Any experience making connections to this type of tubing? Sharkbite fittings? PEX fittings? Or shall I try buying new polypropylene compression fittings?

[goboatingnow]

Push fit shark bite typically.

[Alex A]

I personally had a good experience with PEX-A cold expansion fittings. The tubing is flexible, have greater flow, and they do not leak.

[fourlyons]

Originally Posted by Jammer

New to me boat with some freshwater plumbing problems. The existing tubing appears to be polypropylene. The boat was built in 1999 which was after polybutylene pipe was discontinued but before PEX was widely available, so that makes sense. The tubing is terminated with compression fittings, like the one in the photo, that use a stainless steel "grabber" ring together with a rubber cone washer. In a few cases, polybutylene (Qest) fittings have been retrofitted.


I have a number of plumbing repairs to complete. I have to repipe the connections to the water pump, add a bypass to the water heater, and replace some fixtures. The fittings are deteriorated with the rubber washers not remaining supple enough to reuse reliably. I will be replacing portions of the plumbing with PEX as I go but do not wish to replace every water line on the boat at this point.


Any experience making connections to this type of tubing? Sharkbite fittings? PEX fittings? Or shall I try buying new polypropylene compression fittings?

Yes, I have used the Sharkbite fittings successfully with the polypropylene tubing.

[ggray]

You can get the fittings you now have from US Plastics

https://www.usplastic.com/