I have a 1998 Mercury 225 EFI on my boat. It's always ran great but it had been randomly giving trouble when starting. It would start great almost every time while out fishing, but some of the cranks would be a very quiet winding noise. Then I'd try again and it'd start right up. This would happen about every 6 or 7 cranks. Finally one day while out, this very quiet winding sound is all it would do, every attempt to start. My guess is something to do with the starter or batteries but wanted to ask for advice here. I found out shortly after that my onboard charger hadn't been working, even though it showed my batteries were charged. Haven't had the boat out since I charged batteries with different charger. Think low batteries could've been the problem? Thanks in advance.