Lawn Mower Battery with Trolling Motor?

[7lazy77]

I recently purchased a 13' aluminum boat. It has a 15 hp Johnson with an electric start powered by a "lawn & garden" battery. I have a 54# thrust Minn Kota trolling motor that I would like to use on the boat too. To keep the weight down, can I operate the trolling motor from the 12v lawn & garden battery? If so, what are the pro's & con's? What can I expect the run time to be (I know there are a lot of factors in determining this, but just looking for some general information). Thanks

 

[Silvertip]

Re: Lawn Mower Battery with Trolling Motor?

While the garden tractor battery will be fine for starting the engine, it will last about 10 minutes running a trolling motor. A 54# thrust motor is going to draw a maximum of about 46 amps. Even at half speed the motor would kill that battery in a matter of minutes. Just because it is a battery and just because it provides 12 volts, run time is determined by current (not voltage) draw and the capacity of the battery.