OX-66 V6 Engine. Starter problems. Bendix would not engage the flywheel. It would spin, but not kick out far enough to crank the engine. What did I do? Spent alot of money unnecessarily. I bought two new batteries. New Starter. We're up to $500 bucks here now. I put in the new starter, and still all the Bendix drive did was spin without engaging the flywheel. I called my local Yamaha expert, who was nice enough to take a swing by. He found the problems in under 1 minute. The battery cable that is all part of that thick group of wires coming OUT of the engine and going through the hull was corroded and looked like it was cut. It was only hanging together by about 2 strands of copper wire. So enough voltage to turn the bendix but not kick it out all the way. The boat is 20 years old, so stuff happens. Everyone I asked for opinions said that the cable was the problem most of the time. Just hard to see where the breaks occur.
As an aside, I bought a new Masco starter, which fit perfectly. Seems to be of high quality machining on the outside. Inside the box was a slip of paper that said, "75% of starters that are returned to us have nothing wrong with them". Sort of a caution to check your wiring and other potential trouble spots. Had same issues with my old lawn tractor. Wasn't the starter - it was a safety interlock.
As an aside, I bought a new Masco starter, which fit perfectly. Seems to be of high quality machining on the outside. Inside the box was a slip of paper that said, "75% of starters that are returned to us have nothing wrong with them". Sort of a caution to check your wiring and other potential trouble spots. Had same issues with my old lawn tractor. Wasn't the starter - it was a safety interlock.