Mercury - Gen I Throttle and Shift Cable 28 Foot Mechanical Engine Control 8M0082501. The Mercury Gen I Throttle and Shift Cable (28 Foot / 8.5 m) is designed for boats using traditional Mercury Gen I mechanical control systems where long routing distance is required. This cable connects the control box to the engine to deliver direct, responsive throttle and shift movement without electronic involvement. The 28-foot length is ideal for wide-beam boats, deeper hulls, and long helm-to-engine layo