of bolts 22 shaft 24 extends to the surface through pipe 18 and is supported by bearings 26 and 28 in the pump housing impeller 30 is fixed for rotation with shaft 24 impeller 30 includes flow passageways 32 to enable centrifugal pumping vanes 33 are provided between lower housing 14 and inner lower housing 17 to guide fluid flow to passageways 32 in impeller 30 the suction valve of the present invention includes disk shaped closure element 34 mounted for movement within the housing defined by upper housing 12 lower housing 14 and housing end 20 closure element 34 is movable between an open position shown in fig1 and a closed position shown in dotted lines in fig1 a resilient seal 36 is retained by housing end 20 around inlet opening 21 lip 38 on closure element 34 is provided for engagement with resilient seal 36 the mechanical opening closing linkage includes bell crank lever 40 pivotally mounted at pivot point 42 a centrally located arm 44 on closure element 34 includes an elongated slot 46 bell crank 40 includes a finger 48 at one end thereof which engages slot 46 in arm 44 fins 49 in housing end 20 provide.