Skipperpete has it correct:
- the arrows on the front casting of the BW 71c are to index the pump rotation to the engine rotation....they have nothing to do with output shaft rotation
- running the transmission with the shift lever in the reverse position while the boat is traveling forward risks clutch pack damage. The “forward” clutch pack is much more robust than the reverse pack, and should be used for forward travel.
- Certain ratio 71 series transmissions have output shaft rotation opposite to the engine rotation, but 1:1 ratio transmissions always rotate the same as the engine when the shift lever is in the “forward” position.
That leaves you with two options:
- the propeller hand has been changed, or was never correct to begin with
- the Walters V drive has been changed or was never correct to begin with
Close coupled and remote
Walters V drives are available with or without an idler gear in the output gear train, so opposite rotation can be achieved by using different V drives. This was very convenient for boat builders making twin engine power boats years ago. They needed only stock one type of engine/ transmission package and could get opposite rotation with the v-drive. Today most close coupled V drives rotate either direction with full power and equal ratios.