Advice for new boat please

[mikejjmay]

Hi all,

So ive had small aluminum fishing boats so far, just using the battery for starting, etc. My wife talked me into a nice runabout now, and I have a question.

The boat has a stereo, and I will be wiring in some marine outlets for cell charging, ipod, etc. The stereo is a 2 speaker system, not a huge amp/multi speaker tower like on some wakeboard boats.

Should I be concerned about battery drain? Im thinking of picking up a brand new deep cycle right off the start, but how long could I run that stereo for and be sure to have enough juice to crank her over? Two batteries is not really an option, due to space. She likes to park it and sun bathe/swin for a few hours, and im sure would like a radio running.

Could I just carry a car jump starter charged up in case it drains totally? Would that have enough to start her up?

Any recommendations on the size battery i should get, and how many cranking amps for the battery and jump starter pack?

The boat is a 17' with a 110 johnson outboard. Thanks in advance!

 

[jkust]

Re: Advice for new boat please

With such a basic system, you'd be suprised how long your marine battery will last. Much, much longer than a car battery. Just picking one up and you will realize how unbelievably heavy they are with their extra plates. Adding subs will cut that time down. Here's what I'd do if I was in your shoes given the lack of second battery space...first since I don't know anything about the boat verify the age of the battery and address if needed. Second, It's not a bad idea to always carry a back up battery pack. They are heavy and take up valuable storage space in a small bowrider. Any version will start your boat. At minimum get a set of really long jumper cables and some paddels. Do you have a depth finder on the boat? They will many times have a guage on them that will tell you the exact voltage in the battery and alarm you if the voltage drops to a certain point. In reality the interesting thing is we almost never use the stereo in the boat as the quiet is nicer. I couldn't be comfortable going about my business not knowing how much battery I have left or that I have a means to get the engine running.

 

[Star]

Re: Advice for new boat please

In my opinion a separate deep cycle is a must!!! Ditto on quiet is better!!! Be sure to fuse the main feed. Also a switch to feed your starter circuit because you want to keep them separate except for emergency starts. A separate onboard charger is also needed to charge the deep cycle because the charge system in most outboards will not be enough.

 

[Silvertip]

Re: Advice for new boat please

On that boat with that electrical load just install a group 27, 29, or 31 deep cycle and forget the second battery, switches, ACRs and the associated wiring. If you still feel uncomfortable, then a jump start box is all you need. To test how long your battery will last with the radio on, turn on the radio in your car. Let it run for 4 - 5 hours. If the battery is in reasonable shape it will still start the car. A deep cycle battery has a "Reserve Minutes" number on it. For a group 27 that number is in the 180 minute range. That means the battery will provide 23 (or 25) amps (which is the test load) for 180 minutes or 3 hours. The radio in your boat draws nowhere near that amount of current so lets use 5 amps. 5 amps is 1/5 of 25 so multiply the 3 hours by 5 which provides 15 hours of music. That also does not mean the battery is dead. It just means it can no longer deliver 23 or 25 amps. It will still start the engine.

 

[mikejjmay]

Re: Advice for new boat please

Very useful information about the reserve time, thank you!

I think I will buy the biggest deep cell I can afford, and still have a jump box with a compressor built in (for blowing up inflatables, charging cell in an emergency, and jumping myself or other stranded boats).

Any issues using a deep cycle battery as a starting battery?