76 Evinrude 85 horsepower not enough cranking amps

[jafitzwater]

I have a 76 85 horsepower Evinrude that has currently two batteries Connected. 1 battery is a 27d marine deep cycle and the other one is a 24 deep cycle marine battery. The problem I am having is when the batteries are fully charged the motor will turn over perfectly however when I stop at the perfect fishing spot and turn the trolling motor on and the fish finders and use the bilge pump then want to move again the motor won't start (this is after about an hour). I have to pull start it, however after driving with the motor running again I can Turn it off and start it right up again.

The 24 size batter has all the electronics and accessories on it and is linked to the motor and the 27d is linked to the 24 size battery via battery cables and also runs the trolling motor connections.

I'm trying to figure out why I'm running out of juice with these size batteries and only running a couple of things.

The trolling motor is a 46# 12 motor guide

Any ideas? Is the wiring hookup not right?

Also all connections are sparkly clean just redone.

 

[Triangleboater]

Re: 76 Evinrude 85 horsepower not enough cranking amps

I think something is fishy in your wiring. If I were you, I would get a battery switch and hook up the batteries that that. One of the switches that allows you to choose between battery A or B or both. That way you could switch to one battery while fishing, then the other to start it. Then after it's running switch to both so it will charge both.

I have never personally owned a switch like that but I do believe it will suit your needs.

Just my $.02 a personally more knowledgable than me in this matter I am sure will chime in. I think a lot of people have two different systems for their batteries. One for the starting battery and electronics and then one for their trolling motor. Just charge the trolling motor battery when you get home from fishing.

 

[greenbush future]

Re: 76 Evinrude 85 horsepower not enough cranking amps

Cranking battery should not be part of your accessory (trolling) system. Does your outboard motor have an alternator?
That's what the switching systems are for so you can chose which battery you want to run down, w/o killing your cranking battery. I have 1 dedicated cranking battery, and then 2 trolling batteries for my 24 volt trolling Min Kota . They are never all used together while out on the water, I charge my trolling batteries with an on-board charging system because they will only last a few trips out before they need more charging. So two separate systems that I can shut off or combine as I see fit. I purchased the switch (Perko) because most boats eventually will get a short that will drain one or all of your batteries without the switch. Hope this helps you.

 

[MH Hawker]

Re: 76 Evinrude 85 horsepower not enough cranking amps

Have you loaded tested the battery's, that would be the first step followed by cleaning and polishing ever connection no matter how good one looks. But it sounds like a cell is failing. Separating a trolling from the cranking systems is all ways a good idea or a battery switch.

 

[gm280]

Re: 76 Evinrude 85 horsepower not enough cranking amps

I would run only the O/B off of one battery and keep the other separated for the trolling motor and all accessories. That way there is little chance to run down your cranking battery while out on the water having a good time. but that is just me and my ideas... If you can't crank your O/B with one good battery, you do need to clean and test everything in that circuit. Something isn't right there! Bad, loose or corroded connections are surely possible. And if all those things check out good, look at the starter, could need new brushes and bearings!

 

[jafitzwater]

Re: 76 Evinrude 85 horsepower not enough cranking amps

Thanks for the advice! Separated the two batteries and took the boat out Tonight worked FLAWLESS. Who knew a 12v trolling motor would cripple 2 batteries so fast!

Thanks again

 

[MH Hawker]

Re: 76 Evinrude 85 horsepower not enough cranking amps

They can draw up to 55 amps at max speed and on high you may get 3 hours out of one.

 

[H20Rat]

Re: 76 Evinrude 85 horsepower not enough cranking amps

Connecting 2 different size batteries together is a very good recipe for how to kill two batteries! Don't do it... Glad the problem worked out, and as someone mentioned, that engine puts out next to nothing for charging power. You will probably want to invest in an on-board battery charger that you can plug in after a day of fishing.

 

[Texasmark]

Re: 76 Evinrude 85 horsepower not enough cranking amps

Agree with the comments. I don't like the idea of having to crank my engine by hand so it gets it's own size 24 batt. My TM and all the other goodies get their own set of batteries 2 27s min. Learned this the hard way. The engine recharges the 24. The rest just have to make do.

Mark

 

[The Revenge]

Re: 76 Evinrude 85 horsepower not enough cranking amps

You should have a cranking battery for your start battery. You have two deep cycles.
Also think about adding one of these to your setup.
Mini Add-A-Battery Kit - 65A - Blue Sea Systems