Marine cranking/starting or deep cycle?

[irv]

I am currently in the need of a cranking battery for my 07 90 H/P Merc 4 stroke and I am unsure if I should just get a dedicated automotivr starting battery, a Marine starting battery or just go with a deep cycle dual battery??
My boat has 2 batteries, one for trolling and accessories and the other which I just use strictly for starting, which is what I need now.

I was/am thinking of just buying a regular cranking/starting car type battery but will it last and be able to withstand occasional rough conditions at times?

I just seen a dedicated Marine Starting battery from Interstate and I am currently leaning that way as well but I obviously need some advice.
Also, around what amount of CC amps will I need? I don't use this boat/engine in the cold weather intentionally, only spring/summer/fall with the majority being summer. June, July and August.

Thanks in advance.

 

[ripcord]

Marine starting batteries supposedly have thicker plates and are better able to withstand deeper discharging with less damage. Since boats tend to sit much longer than cars this is an advantage. They are not true deep cycle batteries, though. Their design trades peak cranking amps for deeper cycling ability, but they will still be damaged by deep discharges.

True deep cycle batteries on the other hand will not last long under the high power draws starting an engine requires. They are designed with entirely different parameters.

Costco sells Interstate group 27 and 24 marine starting batteries for about the same price as regular automotive batteries and that's what I would probably go with.

 

[irv]

Originally Posted by ripcord
Marine starting batteries supposedly have thicker plates and are better able to withstand deeper discharging with less damage. Since boats tend to sit much longer than cars this is an advantage. They are not true deep cycle batteries, though. Their design trades peak cranking amps for deeper cycling ability, but they will still be damaged by deep discharges.

True deep cycle batteries on the other hand will not last long under the high power draws starting an engine requires. They are designed with entirely different parameters.

Costco sells Interstate group 27 and 24 marine starting batteries for about the same price as regular automotive batteries and that's what I would probably go with.


That's what I was thinking, they are just somewhat tougher for marine applications.

My prior/dead, no longer good battery was a deep cycle and it lasted quite a few years and I believe at that time, the marina told me it is good for both cranking and deep cycle/accessory use? I am not sure if I was fed a line or not, however?

I checked our Costco up here (Canada) and all I could see is their Kirkland brand and Optima batteries, no Interstate? I'll look again.

Thanks for the info, I appreciate it.

 

[spasm3]

Are you limited on battery physical size? Do you have any accessories that run off the starting battery side? If just for starting, I would get the biggest physical battery that will fit, with the lowest CCA that meets your needs.
( theory here is that higher CCA batteries have more plates in a give space, so they are thinner I.E more susceptible to vibration/damage).

Can't guess at required amps, look for the model manual online, or call a boat shop. Perhaps look at what battery model is in it now, and check those specs.

 

[irv]

Originally Posted by spasm3
Are you limited on battery physical size? Do you have any accessories that run off the starting battery side? If just for starting, I would get the biggest physical battery that will fit, with the lowest CCA that meets your needs.
( theory here is that higher CCA batteries have more plates in a give space, so they are thinner I.E more susceptible to vibration/damage).

Can't guess at required amps, look for the model manual online, or call a boat shop. Perhaps look at what battery model is in it now, and check those specs.


I am somewhat limited in size as both batteries fit in a prefabricated tray and are hidden from view in a compartment.

Nothing else runs off my starting battery, but it does allow for trim and tilt functions. My other deep cycle battery runs my radio, fish finder, and accessory lights when needed.
My engine requires: (copy and paste): 350 CCA (750 MCA) ABOVE 32°F ABOVE 32°F ABOVE 32°F ABOVE 32°F
above 32ºF 24M5 24M5, 24M6, 24M7, 8A24M 9A34M, 9A31 141,
750 CCA below 32ºF
So with that being said, I am not strongly leaning towards this Interstate 24M-HD dedicated starting battery, which has 500 CCA and 625 CA https://www.interstatebatteries.com...ubcategoryKey=&ignorecategoryid=true

Thoughts?

 

[spasm3]

I like deka/east penn batteries. I have used several deep cycle on my travel trailers with good service. Others can chime in but i think this one is made by east penn.

https://www.oreillyauto.com/detail/...chevrolet/avalanche-1500?q=24m&pos=3

 

[irv]

Originally Posted by spasm3
I like deka/east penn batteries. I have used several deep cycle on my travel trailers with good service. Others can chime in but i think this one is made by east penn.

https://www.oreillyauto.com/detail/...chevrolet/avalanche-1500?q=24m&pos=3


I'm unsure what is all available up here compared to the U.S. but I am currently using 1 Interstate and 1 Car Quest battery in my trailer (soon to be 2 CQ's)
So far I have had good luck with both brands but I do know the Interstates hold their charge better than the CQ's. I can get CQ's at the mechanics rate as my bud practically runs a store, but they no longer carry Interstates either. I have also noticed, even with his discount, I can now find parts, etc sometimes cheaper at other places. There is only so much he can do as they don't offer price match, especially when its from a different supplier/manu, and he knows this and doesn't blame me for shopping elsewhere at times.

 

[meadows]

Go to sams for deka/East Penn

 

[ripcord]

Originally Posted by irv
So with that being said, I am not strongly leaning towards this Interstate 24M-HD dedicated starting battery, which has 500 CCA and 625 CA https://www.interstatebatteries.com...ubcategoryKey=&ignorecategoryid=true

Thoughts?

That looks suspiciously like the battery they sell at my local Costco for $80.

 

[GSCJR]

I have never seen Interstate around here at Costco. As you said irv, it's either Optima or Kirkland. Check out Costco.ca, they also have marine/AGM batteries there.

 

[Snagglefoot]

I'm running a Walmart Everstart Marine/RV deep cycle with 550 CCA and 120 minute reserve capacity. Never missed a start. Since it's a single battery I like the idea and having a deep cycle to power the stereo or the fish finder.

 

[Snagglefoot]

Walmart Everstart:

 

[NYEngineer]

Ive been around boats since Im a kid. Start the engine with a starting battery. Run your electronics and such with a deep cycle.

I cannot remember why but my friend ran a battery store for thirty years on Long Island. I know he didnt push combination deep cycle and starting batteries. Ill ask him why and post back.

 

[kc8adu]

a marine starting is a regular starting battery with the stud/nuts terminals along with posts.
if you dont need the studs/nuts just buy a cheaper starting battery.
no difference i could see looking inside 2 of the same brand/cca.
a real deep cycle has fewer but thicker plates.
and almost always has caps so you can add water.
they are antimony rather than calcium and will use water.

 

[Driz]

Originally Posted by ripcord
Originally Posted by irv
So with that being said, I am not strongly leaning towards this Interstate 24M-HD dedicated starting battery, which has 500 CCA and 625 CA https://www.interstatebatteries.com...ubcategoryKey=&ignorecategoryid=true

Thoughts?

That looks suspiciously like the battery they sell at my local Costco for $80.

I saw those at Wallymart. The just don't look anything like the I interstates I Have. They remind me of the cheapo lawn mower batteries that never seem to last. Then I saw the label , 12 months....🥴..no thanks. My usual interstates last 6-7 years even in intermittent service.

 

[irv]

Originally Posted by NYEngineer
Ive been around boats since Im a kid. Start the engine with a starting battery. Run your electronics and such with a deep cycle.

I cannot remember why but my friend ran a battery store for thirty years on Long Island. I know he didnt push combination deep cycle and starting batteries. Ill ask him why and post back.


I think that is what I am going to do, just purchase the starting battery and be done with it.

Originally Posted by kc8adu
a marine starting is a regular starting battery with the stud/nuts terminals along with posts.
if you dont need the studs/nuts just buy a cheaper starting battery.
no difference i could see looking inside 2 of the same brand/cca.
a real deep cycle has fewer but thicker plates.
and almost always has caps so you can add water.
they are antimony rather than calcium and will use water.


I believe, although I could be wrong, but I thought I read somewhere where this marine starting battery is a little tougher than just a regular automotive starting battery?
I am hoping to purchase/order one Tuesday at a local parts store. I am real curious on the price up here but what are you going to do?

I know there are likely other good/decent batteries out there, but like I mentioned, I like Interstate and have had good luck with them so I think that is who I am just going to stick with.

I appreciate all the help/info.

 

[JHZR2]

Originally Posted by NYEngineer
Ive been around boats since Im a kid. Start the engine with a starting battery. Run your electronics and such with a deep cycle.

I cannot remember why but my friend ran a battery store for thirty years on Long Island. I know he didnt push combination deep cycle and starting batteries. Ill ask him why and post back.


Not a good idea to combine. Batteries should be matched. This is how you cause a fire - yes, lead acid batteries can burn.

Unless somehow auctioneered/controlled/switch isolated... But a manual switch leaves for human error.

Putting two batteries in parallel, of different sizes and impedances, means that one will always preferentially take charge over the other, and the imbalance can cause overcharge or other issues.

If totally isolated, such that there is a switch, or two charging supplies, or something like that, it could be OK, but one has to be very careful.

Having a switch that allows you to select between battery 1, 2 and both in parallel is probably OK, assuming that you can manage loads, AND, that you have some sort of charger that will individually charge each battery from main power when back at home, so they stay roughly the same condition.

This way you can keep one for cranking, one for hotel loads, and isolate the cranking one from the other so that you always reserve power to get back home.

 

[4WD]

I have a Perko switch on my cranking battery … just replace every 3 years …
but have always carried an un used spare (cheaper) battery … they last about 5 years like that … and when I try to charge them they seldom need much of a top up since they don't touch the "parasites" …

I go up in some back lakes where many other boats can't go that shallow … so tend to be conservative

 

[SwampSurvivor]

I am using a group 27 DC on my F-350 . It has sat for weeks and started right up.

Except when I leave the brake controller plugged. But every battery does that.