Charging system on outboard Johnson 88 HP

[SalmonSlayer]

I have an outboard Johnson 88hp motor with a two battery set-up. I bought the boat like this so I cannot tell ya how it's wired. I do know there is a solenoid linking the two batteries together that "clicks" when I turn the key to accessory position. I also know that if the top battery (the one where all my accessories are hooked up) is dead, the motor will not start. I have not tried starting just from the bottom battery but I assume it would work fine. Also, I noticed that when the top battery is dead, the depth finder cuts out when an electric downrigger is pulling up the weight...then comes right back on when the rigger is stopped.

My question is this: Are both batteries being charged by the alternator or is only the first one is being charged??? Is this the correct setup I should be running? Or should I do away with the solenoid and simply run one battery for starting and one battery for accessories that gets put on the charger every night? :confused:

Thanks for all the input!

[TONGA]

any chance you can draw us a diagram of how it's wired?
Also never try to run or charge a dead battery with the charging system on that engine,you will put big hurt on your stator,so I hope it is not wired to charge that dead battery,,,,
You may want to pull the motor cover and look at the engine case up under the flywheel and see if there is any goo leaking down the case?

[SalmonSlayer]

Tonga,

No diagram, but here's how it's wired:

Negative of top battery to negative of bottom battery.

Positive of top battery to solenoid, positive of bottom battery to solenoid. The solenoid is activated when the ignition is turned to the "on" position. There's also a small positive and negative feed wires to the solenoid.

My motor is wired directly to the bottom battery...and will start even when there is no top battery hooked up. The bilge is the same way.

All other accessories (depth finder, radio, 4 downriggers) are wired directly to the top battery.

Hope this helps "visualize" the set-up.

[Wannafish]

I can't help with the answer on this much, only because I have no idea why the solenoid between the batteries?
I was considering adding a 2nd battery to my boat,in parallel as yours are, because of the addition of 4 elec. Downriggers, and their draw on the battery while running only the kicker.
My thinking went that the charging of any batteries would occur on the run back to harbor, with a little touchup at home after fishing.
After reading your post on the solenoid, it got meto rethinking, and will the "big" motor outboard charge both batteries, connected in parallel for a 12 volt system?
Need a book on wiring somewhere, better I go check the library?

[TONGA]

so what you are saying is the solenoid connects the 2 batteries together when you turn the key?

[MSUICEMAN]

if the top battery is dead and you connect another one in parallel it acts as a capacitor, which means it eats all the power and therefore nothing would happen, which might also be a problem leading to the problem.

Batteries hooked in parallel should have an equal output of volts but a larger capacity (amp-hours). and yes, they should be charged by the motor at the exact same rate.

steve

[FishTales]

You have two batteries connected together and don't know if your getting a good charge, then you should try using an isolator to correct this problem.
By using an isolator, you will only charge the battery that needs it and if you have a bad battery it won't kill the good one,
You can read about isolators and how they work, just click on the link.

Battery Isolator (http://www.surepower.com/Products/batiso.asp)