Diesel engines need no electric supply to keep going, and usually have ample power to drive a substantial bilge pump as well as propelling the boat.

Usually, there is no need to run the bilge pump continuously, so the pump is driven via an integral clutch, which allows the pulley on the pump to rotate without turning the pump itself. Fitted with a manual clutch, the pump is engaged by an attached lever. With an electromagnetic clutch using the boat's 12 or 24 volt D.C. electric supply, the pump can be operated remotely, usually from the helm.

JABSCO manual and electromagnetic clutch pumps are powerful engine-driven units. These tough and fully-serviceable belt-driven pumps will self-prime rapidly and work continuously over a wide engine speed range. Installed in innumerable fishing boats and other workboats of all kinds, JABSCO clutch pumps are also popular in larger leisure vessels.