Trolling motor battery question

[poorbiker]

I bought this boat and it came with (2) trolling motors and a 3 bank charger. The owner took the trolling motor with. I picked up a real cheap trolling motor. 50# 12 volt minnkota. How long does a trolling battery last. I charged up the batteries and went out and tried it last nite. I would only get about a hour of run time per a battery. Ran the trolling motor about 3/4 speed. Is this typical or could the batteries be no good. No idea how old they are.

[korn_fish]

Lots of factors here. Are they deep marine batteries, combo deep marine/starting, or just starting batteries? If they are deep marine, how many AMP hours are they.

Also, your trolling motor may not be efficient since it is older.

[poorbiker]

They are deep cycle batteries. 850 marine cranking amps with 95 reserve. No idea how old they are. The trolling motor is 4 years old.

[ZapBranigan]

Not sure if #50 means 50lbs thrust or model 50 or what but for a point of reference I get 3 days of running 14hrs per day on and off but a good share in high speed on an old 28lbs of thrust bow mounted Minn Kota purchased back in the early 80's. I would get at least 20 hours on std deep cycle 105 amp battery a few years ago. But in the last couple of years I opicked up a Optima deep cycle cylindar shaped battery and I haven't found the end of use. I have only run 36 hrs of fishing but the indicators shows I have half the charge still left. Man I am pleased with that battery. Going on it's third year now. So well see how many I can get out of it. The old wet cells used to last me 3 to 4 years before they wouldn't work as well then degrade pretty quickly after that.

Good luck with your set up. If you have to pick up another battery I would very strongly recommend am Optima they are sealed and can run upsaide down. I would always pull them in durring the winter and charge them every couple of monthes when not in use.

[ChuckN]

My guess is your batteries are weak. I had a 50lb PD Minn Kota that lasted much more than an hour on a good battery. I would have the battery tested.

I believe some auto part stores will do this, at least the NAPA store I use regularly helped me. They kept the battery for a week to do various load tests and everything came up OK. The problem was my battery charger. So, you never know.. Do a slow low amp charge on each battery for a long time and see if that helps any. It helped my case.

[andy j]

I would also agree that you batteries are on their last leg. I have 2 deep cycle Trojen's that are at least 4 years old and I can easily get a full 12 hour day using them all day in any conditions and still have some juice to spare.

[Fisher Dave]

A 50# trolling motor should last about 2 hours at full speed on a fully charged, 100 amp hour battery... you should have got around 4 hours run time on 3/4 throttle.