OK to use a deep cycle for starting & fish locator?

[Merc25XD]

I have a 1985 25hp Merc on the back of my 14' Lund. Bought a fish sonar just last year and purchased a Marine deep cycle battery to use for the sonar only. Within the last week, I had a electric start and charging system (OEM) put on my 25 Merc. The mechanic stated that the charging system for these units did not put out a lot of amps for charging unless it was run at a higher speed for some time. That being said, I was wondering if I could successfully use the deep cycle battery for starting as well as powering the fish sonar? I hate to go and buy another battery when the newer deep cycle will do the job. All info appreciated. Thanks..

 

[waterinthefuel]

Re: OK to use a deep cycle for starting & fish locator?

You don't need another battery. I use one deep cycle battery in my 14' boat to run everything. It lasts longer than my butt does. No, your engine won't charge that battery well, but it doesn't need to, you can charge it up when you return to the dock.

 

[ebry710]

Re: OK to use a deep cycle for starting & fish locator?

You don't need another battery. I use one deep cycle battery in my 14' boat to run everything. It lasts longer than my butt does. No, your engine won't charge that battery well, but it doesn't need to, you can charge it up when you return to the dock.

I agree. I only have an extra battery (one for starting and one for trolling) just in case. I have never drained my trolling deep cell and always charge it at home.

 

[kandil]

Re: OK to use a deep cycle for starting & fish locator?

Fish finder don't use too much power and if you drain your battery you could always pull start your outboard

 

[Merc25XD]

Re: OK to use a deep cycle for starting & fish locator?

Thank you all for your input. I was going to use my boat tomorrow and fish the Wisconsin River for walleyes BUT my fishing buddy thought it would be too cold. SO..we are going ice fishing in Madison instead.

Thanks again........

 

[rtpassini]

Re: OK to use a deep cycle for starting & fish locator?

the wisconsin river doesn freeze over? im waiting for the fox to open up for white bass run! woooot.

 

[Merc25XD]

Re: OK to use a deep cycle for starting & fish locator?

Many parts if not all of the Wisconsin River freeze solid. Also many people ice fish the Wisconsin just below the dam in Wisconsin Dells. Prairie Du Sac and Petenwell dam areas are now open for boat fishing. I too fish the white bass run in our state. Great fun and great eating.

 

[mthieme]

Re: OK to use a deep cycle for starting & fish locator?

I have an electric start 35 with a FF. The charging circuit didn't work at all last year. Once a month, I had to charge the battery...and it was an old battery of unknown origin too.

 

[mphy98]

Re: OK to use a deep cycle for starting & fish locator?

two batteries are always better than one, one will do your job, but i always believe in a backup on the water

 

[Merc25XD]

Re: OK to use a deep cycle for starting & fish locator?

I think that 2 batteries on my 14' fishing boat would be overkill. Remember that I can still start my motor with the pull cord, battery or not.

 

[triumphrick]

Re: OK to use a deep cycle for starting & fish locator?

Thank you all for your input. I was going to use my boat tomorrow and fish the Wisconsin River for walleyes BUT my fishing buddy thought it would be too cold. SO..we are going ice fishing in Madison instead. Thanks again........

Whew.....those are some choices I'm glad I don't have to make!!

 

[sschefer]

Re: OK to use a deep cycle for starting & fish locator?

One battery is all you need. It's only a 20 and you still have a pull start so who cares if it dies on you or not. It won't hurt the battery with that little starter. The mechanic was right, you only produce about 6 amps max so just make sure its fully charged when you leave the doc and you'll be fine.

 

[SKEETR]

Re: OK to use a deep cycle for starting & fish locator?

When I had my boat starting off my deep cell it would shut down the fishfinder when I started the motor. I think it drew enough amps to cause this. I didn't like the idea of rebooting my gps every time I moved to a new fishing hole so I installed a second battery.

 

[waterinthefuel]

Re: OK to use a deep cycle for starting & fish locator?

That's an indication of a weak battery. My motorcycle does the same thing if the battery is weak. A good deep cycle should easily handle the starter motor for any engine on the water.

 

[Merc25XD]

Re: OK to use a deep cycle for starting & fish locator?

Just to let you know......I took my boat out and went fishing yesterday. I was apprehensive as to how my new battery hook up for the electric start and locator was going to perform. Remember that I just hooked up the leads for the electric starter and locator directly to the freshly charged deep cycle battery. I used my new electric starter and fired up my Merc. Amazing. Let it warm up a bit, then turned on the Humminbird locator. The locator has a volt indicator on it and I was paying a lot of attention to that reading. It was a 1/2 mile trip up to the dam where I was going to fish so I would be able to get a good idea of what was to follow. The (Wisconsin) river being very shallow this time of the year, I was not able to get up much speed because I was worried about hitting rock obstructions in the water. So I put her in gear and slowly motored north. I watch the volt gauge climb upwards toward of 16 volts !! HOLY COW ! Talk about pushing out the amps. Good or bad ? I must have started the motor about 10 times, moving around looking for the walleyes. I left the locator on for 5 hours straight. The voltage stayed between 12.4 & 12.7 or so. Every time I moved, I always watched the volt meter. The volt value would increase each time I started the motor, even though I would just hardly give it any gas to move to another location. After 5 hours of unsuccessful fishing, I headed back to the launch. 2 hours later, when I got home, I was anxious to check the battery status, because I was sure it was in need of a good charge. Well, to my surprise, my battery tester stated that the battery was fully charged and did not need to be charged !! I double checked it again...it was true. Sorry for the long post......

 

[Merc25XD]

Re: OK to use a deep cycle for starting & fish locator?

Here is a pic from yesterday at the dam on the Wisconsin River. Notice the electric start button on the tiller handle.

 

[waterinthefuel]

Re: OK to use a deep cycle for starting & fish locator?

Thats normal. My 28 Johnson does the same thing. It's called an unregulated charging system. It won't hurt anything. Nice little rig you got.