Those blue and red fresh water couplings

[brewster16]

So, during winterizing of my fresh water plumbing system it seems that the coupling (white plastic spin knob) from the blue tube to hot water heater is stripped. Anyone know how to replace it so I can make a tight connection? Those tubes are stiff and that plastic knurled piece's threads are NOT catching no matter how much I try. Thanks

 

[JimG]

That pluming is similar to PEX that you can get a Lowe's or Home Depot... but Sea Ray used the metric version.
So look here:
http://www.fpmarine.com/Scandvik-Plumbing-p/10026-hose-adapter.htm

or maybe this:

http://www.fpmarine.com/Whale-and-SeaTech-quick-connect-fittings-p/whale adapter15mm .75fem.htm

 

[Lazy Daze]

Just to double check, before you buy and replace anything, take that short nipple right next door (in the pic) and see if it will screw in. Other than that, good find by Jim!