Originally Posted by nabiul
I'm glad to report that the boat, replacement floorboard and the DIY h connector we made worked like a charm, despite a little water leaking through the one way bilge valve. However there is a slow constant leak through one of the valves, the o-rings are starting to wear out and are cracked. Also the pump is likely dry as a bone inside and very difficult to use; what is a safe lubricant to use on the pump and o-rings?
Probably Buna seals (i.e. standard O-ring material) in the pump. Silicone oil lubricant would probably be best, but is really expensive (and fairly hard to find.) Whatever you use, try to avoid petroleum products (or those with petroleum carriers/propellants/oils), as they tend to break down most rubber materials (both natural [latex] and synthetic [neoprene, Buna-N, EPDM, etc.).
If you can get a damp cotton swab in to the sealing area of the valve, you may just have some sand or other contaminant in there. Worth a shot.