We discovered that the bilge pump, although operational, was literally held together with Sikaflex, and pulling at one of the hoses separated it from the pump. We discovered that the fitting had sheared from the pump and sikaflex had been used to stick it back on.
Hmmm. New bilge pump and hoses fitted, and while we were at it, a new diverter valve to select the bilge to be pumped. Couldn’t do much else this month, as we had lots of other stuff on.