Cranking battery question.

Discussion in 'Boats and Motors' started by Salmonid, Dec 28, 2008.

  1. Looking to replace the main cranking battery on the boat with xmas cash. Whats there is a deep cycle Everstart 400 cold cranking amp battery and I wondered if a bigger battery would help me with constant fish finder and aerators running while catfishing? Right now when I restart the engine, the fish finder turns off because of low power and I have to reseet it and wait a few minutes for the GPS to relocate, its a real pain in the arse.

    I have heard that putting an oversized battery will sometimes break the starter because of too much power but wondered if I went up to a 540 CCA and one with a bigger "reserve" rating would help much or should I rewire the Fish finder and aerators to the trolling batteries(2 up front)? Of course that will drastically cut into the trolling effectiveness when I am chasing bait....

    Thoughts?? Thanks guys, Motor is a Force 90- HP, 1998
  2. Salmonoid-
    you should always run the biggest battery you can afford or fit in your battery box. I have never heard that about beating up the starter. All your electrical systems should have fuses or breakers to prevent any type of system damage from overload/too much voltage. Good luck,Gabe :B

  3. Doctor

    Doctor CJ Cat Attack Pack

    My old boat I ran a starter battery and had the depth finders tied into the starting battery so I could keep an eye on it, used a Perko switch to flip over to a huge D cell battery that I ran everything when fishing, had another huge D cell that would run the lights and trolling motor.

    My new boat I'm getting ready to switch it over has 2 batteries for the 24 volt trolling motor, has a 550 Cranking battery for the main engine, I'm installing a 1000 amp D cell for fishing, utilizing the Perko switch I flip it over and everything except the trolling motor and depthfinders will be running off that huge D cell battery,filling pumps, aerator pumps, Bilge, air pumps for livewell and Akwa-Lung, Grayline pumps and air pumps and lights on the boat for night fishing.

    By separating your high amp items you will not run out of power, no fun being down on the river with battery power failure, been there done that, since switching over to the above system I have never had a problem with loss of power, those big heavy D cells weight like a 100# but they just don't run out of power, plus if you do have a failure, using the Perko you can switch over and start up using the heavy D Cell.

    I'll sacrifice my top end speed on the boat to guarantee I don't run out of power any day.................Doc
  4. Doc, not sure I know what your taking about with the big D cell?? do you have pics or a link to one online?? I like that idea and was what I was thinking about, seperaing everything but the finder/cranking to another power source without giving up the Trolling batteries.

    Thanks guys, Salmonid
  5. Doctor

    Doctor CJ Cat Attack Pack


    Big D Cell is a deep cycle battery like you use on your trolling motor, the one I have on my boat is called a Liberty battery, it is 12 volt 1000 amp hours, my shop inadvertently ordered the wrong size for our UPS system at work they could not be returned and I jumped all over them they weight 83# each, I gave away 8 of these things at DuraCats tournaments back in 2006, I have two for my boat, Larry has one and Bink has one these are like $300.00 batteries and nobody has had one fail yet, just seems like you can never run them down, plus they are fully sealed have 1 inch copper bars inside them they are an AGM battery, I thought about using them on my trolling motor but I use the livewell more than the trolling motor so I left the new ones in place.

    Between this post and the prior post I installed the Perko switch and Battery and wired it in on my new boat I'm now ready to go, I still need to shorten the cables as I have them all rolled up in the back but I have to get some new crimps to do it correctly.

    One thing nice about these Perko switches if your way down river like 40 miles and yes I have been known to run that far one way once you get the motor going you can flip the switch to all or 2 and charge all the batteries on your boat using your big engine, have done that several times on the old boat when we used to fish those all night 12 hour catfish tournaments.

  6. Be sure not to exceed the cranking amps for your motor and yes
    a larger battery with a greater reserve will cure some of your problems.
    A perko switch will allow you to switch batteries but your 90 hp force
    may not put out enough amps to charge your batteries while running.
    I was told that if I had the red stator on my 90 merc that
    it would provide enough amps to charge a dual battery system. Check
    with a marina to see if your motor puts out enough amps before investing
    in a perko. Your aerators must draw a lot of juice.
  7. The aerators are for shad tanks, and the livewells bilge would be running while catfishing ( waiting for hours without having the motor running), then run 10 minutes to the next spot, sit for a hour etc. That is what tends to eat up juice. I never had any probems so far but would like o keep it that way.
    Thanks, ill check the engine stats

  8. I had the same issue with my Mercruiser 5L I/O. The raymarine systems that I use would shut down as soon as I cranked her over. I pulled the main ground to the engine off and cleaned it and replaced the terminator ends with high quality ends soldered then crimped on. I then replaced the leads from the batt pos. terminal to the starter with new heavy duty calbes I made from stock at NAPA. I also installed a DC to DC converter with a 1000amp capacitor. Basically making perfect clean DC power for the sounder, gps, radar and lights. Works GREAT! The DC to DC converter was about 200 and the cap was 89.99 at a local car audio shop. By the way I didn't need the extra stuff that was just my OVERKILL style. When I cleaned and replaced the terminals to the engine the issue was resolved. The problem was a high amount of resitance when the starter was engaged.


    Hope this helps.