motorcycle battery for my 25hp

[freshh2oguy]

Looking to downsize my existing battery to this guy.
No electronics just a 25hp 2stroke merc. Any reason it wouldn't do a good job?

Opinions? Thoughts?

Thanks



hYTX24HL Scorpion 12v 350 CCA Harley HVT-6 AGM

 

[GA_Boater]

Pull or electric start Merc? Does the Merc have a a charging system with a regulator?

 

[freshh2oguy]

Its both elect and pull and yea its got a charging system on it.

 

[Bondo]

Ayuh,.... Welcome Aboard,... I donno, but doubt the motorcycle battery has enough power to use the electric start,....

 

[Grub54891]

Agreed with bondo. You need more amps than a small battery can provide. Even several years ago, My motorcycle battery went south, I picked up a generic replace ment, and it was very hard to start after that. I found out it required a factory specific battery as the aftermarket ones, say they have the amps....but not enough reserve. One kick of the kickstart, it would start every time. Not with the starter though. Go ahead, give it a try, let us know if it works....

 

[freshh2oguy]

The good thing is that I can pull start it if needed.
I just can't imagine that a 25hp motor is more demanding to start than a big Harley.

 

[jbcurt00]

A ballistic battery will do it, but ouch, pricey

 

[GA_Boater]

The good thing is that I can pull start it if needed.
I just can't imagine that a 25hp motor is more demanding to start than a big Harley.

The issue isn't that it's harder to start. It's a question of reserve capacity and small batteries don't have much. If the motor needs a lot of cranking, the battery will be dead in no time. When you get the motor running, the charging system is not robust enough to charge dead or almost dead batteries and can damage the charging system.

Why do you want a smaller battery? If you always pull start, the small battery will be fine. Just don't run it down and expect to charge very fast from the motor or without the possibility of hurting the motor charging system.

 

[PatinIdaho]

Actually i tried this with a old 50hp merc. I used a decent size MC battery if i remember right it was for a 750 Honda. Worked perfectly for a entire summer without a problem. Seemed to have plenty of reserve for starting a flooded engine and the engine would charge it fine
PS.
Must not have been a 750 honda battery. I remember it was around $80bucks.

 

[HT32BSX115]

Looking to downsize my existing battery to this guy.
No electronics just a 25hp 2stroke merc. Any reason it wouldn't do a good job?

Opinions? Thoughts?

Thanks



hYTX24HL Scorpion 12v 350 CCA Harley HVT-6 AGM

Howdy,

I used a battery like that (used Napa Wheel chair battery) in my airplane for 3 or 4 years. It would sit for 6mo (with no charging) and still crank the engine. I use an AGM aircraft battery now but when I changed the battery in my John Deere lawn tractor (about 3 years ago) I went with an AGM wheel chair battery not unlike the wheel chair batteries from Napa Auto Parts
That Battery you are considering is nearly the same as what I have in my tractor. A battery that'll start an 80 cu-in V-twin will spin that 25hp outboard just fine and it will work well. Just ensure that your charging system will do the job.

Cheers,


Rick

 

[airshot]

Yep I have used small wheel chair batteries myself with great success. In fact I use a small deep cycle wheel chair battery for my electric trolling motor in my pond. Will run on low speed for about 1-2 hrs continuous. Got mine online, shipped to my door for less than 50 bucks, sealed so no acid to deal with.

 

[freshh2oguy]

Thanks for the input guys... I assume the charging system will work fine as the current fullsize deep cycle that I use now charges perfectly and I hardly ever have to recharge it (only to top it off).