So i go to run my motor on Saturday and it turns out that the batteries are too weak to turn the motor over. When I turn on the ignition Ill get a click and a weak sound from the starter motor. (BTW im running a dual battery setup and put the battery switch to BOTH to try get it started) My question is, How long does a motor have to be running to charge a battery? I run my motor religiously every week for about 10 minutes. Last time I took the boat out was at the end of march for a full run so i assumed that the batteries were fully charged. Can the batteries slowly drain over this period of time even thought im running it weekly for 10 minutes? Should I be runnig the boat longer to recharge the batteries? Since the last time I took it for a run was only about 2 months ago, it seems odd that the batteries would drain so soon. Im gonna have the batteries checked but if this happens again maybe i have to suspect a bad alternator. One of the batteries was dated 12/2007 so its about 30 months old. Any ideas?