Abstract: An electric trolling motor for propelling a boat and comprising an electric propulsion motor having a substantially cylindrical motor housing and an electric trolling motor end cap for mounting and protecting a transducer therein, the end cap comprising a body portion having a recess integrally formed therein for receiving a transducer in the recess and a transducer removably mounted in the recess, a bore formed in the end cap creating a passageway extending from the exterior of the end cap to the interior of the recess, and a releasable air pressure seal for obturating the passageway and retaining the transducer in the recess when the passageway is obturated, and releasing the air pressure seal when the passageway is opened; also, a novel end cap for electric trolling motors.