best battery for 3.0 merc

[intrepid]

Hi<br /><br /> My battery is about 5 years old , and its about time to consider replacing the old interstate.<br /><br /> Should I get the same type , it's been working well, or should I go for one of those new spiral wound ( blue - deep cycle ) battery?<br /><br />or a wally world eveready one ?<br /><br />Is there any big difference ?<br />thanks<br />

 

[DJ]

Re: best battery for 3.0 merc

Just get the biggest (marine) battery that will fit in your battery box. Make sure the connections are clean and tight and you're good to go.

 

[ThomWV]

Re: best battery for 3.0 merc

I agree completely. The best battery is the biggest battery you can reasonably carry in the boat, and a pair of them is more than twice as good as one of them. I'm also a believer in plain Jane led-acid batterys unless you have some sort of special requirement that drives you to a speciality battery. Its pretty clear that you take care of your batterys, to get 5 years out of them. Most folks just stick them in and forget about them. Its good to hear from a fellow who does more than that.<br /><br />Thom

 

[ZmOz]

Re: best battery for 3.0 merc

What are you using it for? If you're just starting your engine and skiing on a lake for the day, just get a cheap automotive battery. If you're going out in the ocean with lots of electronics and it's your only battery you need an expensive one.

 

[Boatist]

Re: best battery for 3.0 merc

Intrepid<br />My engine is a 3.0L also and for my starting battery I use a group 24 auto battery. Never had one that did not last at least 6 years. You can get a bigger heavier battery for a little more money but I do not think it makes them last any longer. A group 24 will supply more than double the curent needed to run your bildge blower and start your 3.0L motor. If you only have one battery and you fish at anchore with anchore lights on and all the electronics going then I would get a bigger battery, group 27, 29, or 31. <br /><br />If you have any type of electric trolling motor then for sure get as big as will fit and you can afford.

 

[18rabbit]

Re: best battery for 3.0 merc

Boatist – all else being equal, a bigger battery may last longer. The depth of discharge has a tremendous affect on the number of cycles (and thus life) of all lead acid batteries. There is a point of diminishing return if a battery is never discharged by more than 20% of its capacity.<br /><br />Starting batteries benefit from a well maintained engine. The battery doesn’t need to cough up as deep a discharge to get things going. In this case there may not be any noticeable benefit from buying a bigger battery.<br /><br />Intrepid – there is a huge difference in the battery technologies you inquired about. Personally, I’m of the “if it ain’t broke, don’t fix it” school of thought. Whatever your application, if you got 5 years out of a starting battery, I would be less inclined to change anything. And in this case, I agree with Boatist, I would not toss out $$$ for a bigger battery. When it comes time to change the battery, go get yourself another Interstate, same size…and go boating!