"Does the motor not effect the sonar beam that the transducer shoots to the lh side?" Yes it will if the motor is in line with the transducer. It will not shoot through the motor or anything that is in it's way. Simple way to check this would be to lift the motor up and see if it clears up sonar picture to the left while running the trolling motor as the boat will have to be moving to get side imaging to work correctly.
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