Starting problems with the 200hp Yamaha

[spareparts]

Replace both battery cables, the Yamaha cables are made out of fine wire, they work real good for a while, but over the years of use, the wire breaks internally. You may find a place in it that was compromised and allowed water to enter the cables, they turn green and corrode up pretty quick. I see this all the time on older Yamaha engines. Run some new #4 cable(#2 if its a long run) with good cable ends and you'll be ahead of the game