69 Avion wrote:
Trailers made in the 1980s to the mid 1990s used Polybutelene piping. It is the worst junk ever inflicted on the American public. In fact, it is the subject of one of the most expensive product liability lawsuits ever.
Repipe with PEX. I prefer PEX "a" because it flexes better than the others, but it isn't as widely used because it is more money.
X2
I replumbed my old Starcraft (total 50 crimps or so) with PEX and have pressurized the system to 80 psi with no leaks. As Avion says, the butyl pipe is what's working against you. Replace with PEX.