Need help. Boat charging issue

[Ochrod]

Anyone have charging diagram for 2011 RZ2. Think this is first time out with new software load. Noticed crank volts was 11.2 and dropping. House volts was 18.6 and never changed. Anyway crank volts got below 6 and boat died. I removed that battery and put all wires to good battery and got back on trailer. House volts never changed from18.6. Crank volts on the single battery stayed constant at 13.6 which tells me it was charging. And I'm leaving on Thursday for lake of the Ozarks. Help! Where do I start?

[Z1Fan]

Look at mine as chptril convo in electrical ,lotsa info in there , charging system is quite simple

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[Ochrod]

Finally got home and now if weather cools I can start troubleshooting. I did measure voltage across the batt posts, The battery I removed showed 11.7 volts and the one I left in boat that got me back to the ramp yesterday read 12.2V. Not sure how my crank volts on page showed battery drain down to under 6 volts. And both batteries are marine deep cycle. Now I need to chase the cables to see which is house battery and which is crank battery.

Also I tried changing the battery switch from single to both yesterday but nothing changed.


Z1, now that I'm home I am looking through all the electrical posts. I'm sure I'll find what I need.

[Z1Fan]

Booth are deep cycle ? That's not that good , one should be marine starting and house batt should be marine seep cycle , but regardless , 11.7 is a tad low, either it's discharged or a cell has let go

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[Ochrod]

Battery took a charge, will see if it holds in am. Back at 13v now and charger didn't show any faults. Is this what controls the charging of both batteries?

20140803_182626.jpg

I'm wondering if the isolator failed and won't charge the crank battery? I need to put it all back together tomorrow. Does it make sense to check voltage at the battery when running to see if I get an increase in voltage which would say it is charging. If its not I guess put a meter across the isolator? I'm still trying to sort out the power cables.

I have the 2 gauge ground coming from the engine I need to hook up. I'm not sure where the two 4 gauge grounds hook up. I don't see a ground buss bar by the batteries anywhere. I didn't pay attention to which wires I moved and how it was wired yesterday on the water when I had to switch over.

Need to get sorted out tomorrow as I really want to take it to LOTO this weekend for Tige reunion.

[Ochrod]

Another question:

Could the second battery ground be connected to the main battery ground which is connected to the engine? Then the power goes to the battery switch?

[chpthril]

Look at those cables connected to the breakers below the isolator! Look at the rust/corrosion!

Thats a diode isolator. Its a passive device and really doesnt control anything, bit rather allow the alternator charge to pass to the batteries, while preventing a load drawing on the battery, from drawing from the other. Yes, a diod can fail, but unlikely. Probing with the volt meter while the engine is running, will show this.

[chpthril]

Battery B ground is connected to battery A ground, which is connected to the main boat ground. Each batteries' B+ goes to the switch

[Ochrod]

Thanks chpthril, I noticed those and plan on cleaning before installing batteries. Sounds like I'm on the right track for troubleshooting. Start again in the morning

[Z1Fan]

Good call chp , crazy corrosion , how old is the boat? The coorrosion should not be that bad , is water getting in there ?

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[talltigeguy]

Booth are deep cycle ? That's not that good , one should be marine starting and house batt should be marine seep cycle , but regardless , 11.7 is a tad low, either it's discharged or a cell has let go

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It's fine to have both batteries be deep cycle. I personally prefer it that way. One issue I see repeatedly with dual batteries failing prematurely is that when you mix and match 2 types of batteries, then charge them at the same time, you are begging for premature failure of one or the other. A deep cycle will still last a very long time, even when used as a starting battery.

Just because the voltages returned to normalish when the engine was off does not mean that the batteries are OK. If you can run the engine and check the voltages, then that would be ideal. Any 12 volt battery that has actually had 18 volts to it is dead. And batteries that have had 6 volts are going to be dead soon. I would put a charger to your batteries and then take them to Auto Zone and have them tested.

[Ochrod]

Its a 2011. No water getting in there since I bought in March. Not sure of history of first owner. 2nd owner kept garaged

[Ochrod]

Im not convinced the one battery actually had 18v to it. I will be checking tomorrow when everything is connected again. It was the battery I put everything on to get boat back to ramp. The labels on the cables to that one say secondary so I assume that is the house battery?

[Ochrod]

I have hooked up both batteries one at a time. The house volts always reads 18.6. When I turn ignition on the crank volts comes up to 12.3. Regardless of which battery I hook up or which isolator I hook up. Not sure where house battery voltage is read at. Any ideas? Batteries both read 12.3-12.7 on posts

[chpthril]

The house volts always reads 18.6.

Where and how are you reading this with the key not on?