# How Small of a Battery for a 40hp Yamaha?



## BigEasy

My current motor is pull start only with no power T&T. I'm thinking of upgrading to e start with T&T but am not excited about putting a group 27 batter in the boat.

Do any of you guys know what the smallest/lightest battery would be for a new Yamaha 40hp?


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## jmrodandgun

Here is the chart from optima. Personally I think their numbers are slightly overkill but that's just my opinion. Something in the 300 cold cranking amps range would likely be far more CCA than you actually need.

You can get away with a very lightweight cranking battery, especially with a backup pull start. The electric start conversion is a bitch and if it's going to also operate the tilt/trim unit you may want to bump up the amp/hr rating.


*EVINRUDE*
Outboard 25 - 90 hp = 640 - 800 CCA
Outboard 25 - 90 hp = (Extreme Apps)800 - 1000 CCA
Outboard 115 - 250 hp = 675 - 845 CCA
Outboard 115 - 250 hp = (Extreme Apps) 800 - 1000 CCA
extreme apps being very cold temps


*Mercury* 
2-Stroke 6-15, 20/25, 30/40, 40/50 & 60 hp 350- 465 CCA
2-Stroke 75 - 125 hp 450 -525 CCA
4-Stroke 9.9/15 & 25 hp 350- 465 CCA
4-Stroke 30/40, 45/50 hp 350-465 CCA
4-Stroke 30/40, 45/50 hp (Extreme Apps) 750 -1000 CCA
4-Stroke 75/90 350 465 CCA
4-Stroke 75/90 (Extreme Apps) 750 -1000 CCA
V-6 Carb EFI 135/200 & 200/250 hp 490 630 CCA
OptiMax 2.5L/3.0L 750 - 1000 CCA
Verado 135-200hp 800 - 1000 CCA
Verado 200-300hp 800 - 1000 CCA

*Suzuki *
4-Stroke 25 hp and below 330 - 450 CCA
4-Stroke 40 - 140 hp 512 - 650 CCA
4-Stroke 150 - 250 hp 670 - 850 CCA
4-Stroke 300 hp 800 - 1000 CCA

*Yamaha *
2-Stroke 50 hp and below 245 -323 CCA
2-Stroke 60 - 150 hp Carbureted 380- 502 CCA
2-Stroke 2.6L 150 - 200 hp EFI 380 -502 CCA
2-Stroke 3.1L 200 - 250 hp EFI 512- 675 CCA
2-Stroke150 - 300 hp HPDI 512 -675 CCA
4-Stroke F25 and below 245 -323 CCA
4-Stroke F30 - F115 380 - 502 CCA
4-Stroke F150 - F250 512- 675 CCA
4-Stroke F350 750 -950 CCA


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## jfboothe

I have a Shorai Lithium battery on my motorcycle that only weighs a few lbs. I haven't tried it but I can't imagine if it will start my 1100cc high compression twin race bike, it won't start up a a medium sized outboard.


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## jmrodandgun

Those things are like 3 or 4 pounds and 300 CCA. Not horribly expensive either. Other than thinking they are neat, I don't know anything about them. Although I would be interested to see how they hold up under charging conditions.


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## Sublime

On my etec 50 I used a PC-625. 13 pounds 220 CCA.

BUT, when it was cold outside (50 or below) it wouldn't crank. Turns out COLD Cranking Amps mean something. Who Knew ?!?!


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## BigEasy

Yeah the lightweight lithium was what I was hoping for but it seems like it's either a bike battery or jump to a group 24......

Yeah I thought about doing a conversion on my current motor, I don't really need t&t although it would be nice. But I can't find a "kit" to do it and you start pricing the pieces and parts and the economy is just not there.

Thanks for the input.


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## SomaliPirate

I'm starting a 60 Yammy 2 stroke with a Odyssey PC 1100. Starts the motor just fine and runs all my electronics. I think it weighs about 25lbs or so. If you shop around, you can find them cheaper than the Optimas.


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