It seems the coiled hose on “water flossers” or “water jet” oral hygene appliances (I can’t even type that with a straight face) lasts about three years, then fails in a spectacular water spray. Mary’s Interplak cleaner just blew a hose, whereupon I discovered that 3/32 inch ID Tygon tubing is a very snug press fit over the 3.8 mm OD white plastic hose:
The hose blew out during the early part of a protracted snow storm / cold snap, when driving out for a replacement wasn’t going to happen. This fix, ugly though it may be, has been working well enough that we’ll wait for something else to go wrong.
It’s not clear replacing the entire length of hose with Tygon tubing would work as well, because the rigid hose transmits water pressure pulses from the pump to the tip without much damping. We’re not sure how much that matters and, if the Tygon hack outlasts the OEM hose, maybe we’ll try that.
As you might expect, the hose isn’t a replaceable part. In fact, Interplak doesn’t list any replaceable parts, other than the jet tips, which never seem to wear out…