I have a 1993 Evinrude trolling motor. Model number on the foot pedal is BFL4K. What is the output for this model and I do not seem to have the thrust output for even 20lbs on 12 or 24v. What could the problem be? Batteries are hot and seems to be wired correctly. It has been suggested brushes are bad or the armature.??? Please help. I really dont want to scrap this motor.