@LordByron do you know the pumps manufacturer? Do you have a picture?
It is possible that the pump info you seek was added to the boat by the dealer or previous owner.
Here is one type of unit used.
A Whale Gusher Manual Bilge pump.
- Versatility of design - Dual size nozzles for 25 mm (1") or 38 mm (1+") hose to suit your plumbing
- Efficient performance - up to 55 ltrs (14.5 US gals) per minute
Yours may be similar or different.