Mercury - Gen I Throttle and Shift Cable 25 Foot Mechanical Engine Control 8M0082498. The Mercury Gen I Throttle and Shift Cable (25 Foot / 7.6 m) is designed for boats using traditional Mercury Gen I mechanical control systems where maximum routing length is required. This cable connects the control box to the engine to deliver direct, responsive throttle and shift movement without electronic involvement. The 25-foot length is ideal for wide-beam boats, deeper hulls, and long helm-to-engine lay