I've had what I consider to be a slow-cranking engine since I got my boat, along with the occasional key turn with nothing more than a click from the engine area. Replaced the slave solenoid since it was cheap and easy to get to, but that did not remedy the situation. Finally got around to replacing the starter, which I think was the original direct drive type, with a new Arco permanent magnet gear reduction unit. Night and day difference. The slow crank always freaks me out, makes me think the battery is dead, especially when I turn the key and just get a click and nothing else. Original starter, this is a "good" crank. It's even slower when warm, and at times I had to bump the key 2-3 times before it would do anything other than click. New PMGR Arco starter.