# jetski or lawn mower battery



## sbritt23 (Mar 6, 2013)

So I've been tossing around the idea of trying to use a LM or jet ski battery to start up my 94 evinrude 40 can this be done wanting a light weight smal battery in the stern of my boat for cranking, nav lights, bilge pump, and cmc tilt and trim Jack plate any suggestions out there


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## redbug (Mar 6, 2013)

check the requirements for the motor 
how many cold cranking amps does it require?
if you can meet that with the smaller battery then you could try
i dont know if i would trust being out on the water counting on that size battery to start mt big motor


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## JMichael (Mar 6, 2013)

I don't know about a 40 but I'm considering trying the same thing with my 20hp merc. I figure it can't be much different to start my Mercury than it would be to start an 18-20 horse mower. I plan to take the battery off my riding mower this spring just to test with but if it works you can bet I'll go buy one for my motor battery.


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## sbritt23 (Mar 6, 2013)

JMichael said:


> I don't know about a 40 but I'm considering trying the same thing with my 20hp merc. I figure it can't be much different to start my Mercury than it would be to start an 18-20 horse mower. I plan to take the battery off my riding mower this spring just to test with but if it works you can bet I'll go buy one for my motor battery.



My father has a jetski battery on a 4 stroke mercury 20 and it does fine so im pretty sure it would work on yours as well


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## JMichael (Mar 6, 2013)

sbritt23 said:


> My father has a jetski battery on a 4 stroke mercury 20 and it does fine so im pretty sure it would work on yours as well


Great! I'll just plan on getting one come spring then.


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## krawler (Mar 6, 2013)

The big jet ski's are more than 40 hp, so I think you would be okay with a big jet ski battery.


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## moi (Mar 11, 2013)

FWIW I recently converted my 1994 20hp 2 stroke Merc to electric start and installed a "lawnmower" type battery for starting. Works like a charm and behaves like it could crank all day long.


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## lckstckn2smknbrls (Mar 11, 2013)

I just asked this question on Iboats for my 1974 mercury 402 and got the answer of yes.


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## JMichael (Mar 11, 2013)

They say every dog has his day. :mrgreen: My aunt is moving out of state and asked me to come help her clean out her mini storage. We get there and had only loaded a few things when I noticed a brand new mower battery sitting there. It still had the protective cover over the + post. I ask what she had that for and she informed me she got it for the riding mower but the mower stayed with the house so she didn't need it now. Needless to say she didn't have to ask twice if I needed/wanted it. :mrgreen:


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## lovedr79 (Mar 12, 2013)

should be fine. i start my boat with the trolling motor battery  and eliminated the "starting" battery


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