Hello to all fellow boaters! This is my first post and I already have a problem lol ! I have a 1976 Evinrude 25 hp (model 25652e) on a 14 foot jon boat and when the boat starts to plane it sounds like the outboard is hitting a stump. What could that be? I have replaced the woodruff key under the flywheel and I replaced the shear pin at the prop. I actually have the outboard running very well other than this problem. Well, while I'm asking questions, does this outboard have some sort of kill switch? Or can I add a modern kill switch?