What size starting battery do I need?

[BWR1953]

Just picked up a 1985 Mercury 50HP four cylinder with power tilt and trim. I'll be using a 2 battery system in my fishing boat and the cranking battery will only be used to start the motor and for the nav lights. The Mercury engine will only charge the starting battery.

I'll have a deep cycle battery for the trolling motor/depth sounder and it'll be charged separately at home with a regular 120VAC charger.

So how many cranking amps should I shop for?

Thanks for any input!

 

[roscoe]

The smallest one you can find should work.
400 cca or 500 Mca is all you need.

good motor

 

[BWR1953]

The smallest one you can find should work.
400 cca or 500 Mca is all you need.

good motor

Thanks! I'll look for something along that size.

I had a motor just like this one on my 1985 Bass Tracker that I purchased new 30 years ago. Kept the boat 8 years and never did a thing to the motor except put fuel in it, check the lower unit oil once a year and winterize during the cold months. It was an absolutely reliable motor the whole time.

Am very pleased with getting this one. Will be starting a thread on it once I start messing around with getting it running and such.