I have read post here saying that if you have a bad cylinder, you should bore out all the cylinders. Why I ask this is that 7 years ago I blew one of the bottom pistons and had pieces missing out of the other bottom piston. Dont know what caused the problem. Anyway I baught a good shop manual for it and worked the engine over. The bottom left cylinder had to be bored out 30/1000 but the other wasnt damaged. Had the other three cylinders honed out and I replaced the bottom right cylinder with a new stock piston and new rings for all cylinder. It sounds like a poor boy repair and it was. I've since bought an 05 Pro-Gator with a 225 HO E-tech on it, but gave the old boat to my son and the engine still runs like a top. So for a fellow with limited funds, why do do you say bore all the cylinders out? By the way the boat the 115 is mounted on was an old Kingfisher. If they still built boats I'd be the first to buy one from them. Thats got to be one of the most durable boats I ever owned.