Deep cycle or car battery

buckshot77

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So I just bought a 01 Larson with a 3.0 I/O. It has a deep cycle battery for it. I understand from wrenching on trailers that a deep cycle is a good option. Why on a 4 cylinder car engine would you want a deep cycle???
 

alldodge

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Why on a 4 cylinder car engine would you want a deep cycle???

My comment is why not a DC?

DC bats can be drained further then a starting before they are damaged
A 4 cyl motor doesn't need a lot of current to crank the motor
 

buckshot77

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DC aren't designed to take the hi amperage charge that a non DC is, they work best if drained then trickle charged up or trickle charged like a trailer converter does.
 

dingbat

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The simple answer is economics.

A deep cycle battery is more expense than a starting battery.

Multiple the cost difference by the number of cars built and the answer is obvious ;)
 

Scott Danforth

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most marine deep cycles can be used for starting.
 

Grub54891

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I'd use it, but the other option I'd do, is move that battery to the use as a house battery, and put in a group 27 or 31 for the motor. Add a battery switch and use the deep cycle for running electronics while at anchor.
 

dingbat

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I'd use it, but the other option I'd do, is move that battery to the use as a house battery, and put in a group 27 or 31 for the motor. Add a battery switch and use the deep cycle for running electronics while at anchor.
Unless you have a high HP motor, a grp. 24 starting battery should suffice.
 

H20Rat

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I start my cold blooded 7.5l Ford gas motor in my RV with a group 27 deep cycle, so your boat engine will be fine!
 

Lou C

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the deep cycle should work as long as it has sufficient cranking amps for starting. I've used a pair of gp 27 dual purpose batteries in my '88 Four Winns for years. They give adequate cranking amps but can also hold up to light loads such as running radios and fish finders.
 

Grub54891

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Unless you have a high HP motor, a grp. 24 starting battery should suffice.

This is true, but I prefer a touch of overkill. My current battery group 31 for my 140 is 8 years old, tests just fine. The battery in my other boat, same motor used up a 27 after 3 years. I know, different boat different issues.
 

jimmbo

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If you insist on using DC Batteries, then have 2 or 3 wired together In Parallel, that way they should should be able to supply the High Demands of the Starter Motor. Myself, I will stick to Marine Starting Batteries. not Auto/Truck Batteries. And for those who will take this Bait, there are differences in the parts you can't see(unless you take them apart) between the two
 
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