Battery replacement

[cardude01]

Well I think I screwed up. I recently replaced my 4 house bank batteries with new ones, but I didn't replace my start battery because it seemed to be starting fine.

I tried to start the engine a few minutes ago and it was dead as hell.
I jumped it to the house bank and got the engine started, but now I wonder why the start battery isn't charging. I've been on shore power for days now with the battery charger on.

 

[N4712]

Check the fuses on the charger leads?

 

[Cat Daddy]

Shore power probably only charges the house bank. Engine alternator charges both, house & start. At least that's how I think mine works.

Have you made it to the Keys yet?

Rafe

 

[RT Firefly]

Greetings,
Mr dude. Do the cheap/free tests first. Check and clean all connections, battery electrolyte levels, charger output, fuses etc. If you don't have one, get a battery hydrometer and check state of charge of individual cells. EZ Red Battery Hydrometer: BatteryMart.com You didn't necessarily screw up, it could be your starting batteries "time". 12V batteries can die from one start to the next. 6V batteries just seem to weaken over time and give you some warning.
I'm sure someone who actually knows what they're talking about can give you further advice.

 

[cardude01]

Shore power probably only charges the house bank. Engine alternator charges both, house & start. At least that's how I think mine works.



Have you made it to the Keys yet?



Rafe

Ahhh. If that's true that would explain it.

We leave tamale am.

 

[cardude01]

They are AGM batteries.

 

[BruceK]

So, what happened to the start batt after you ran the engine? Is it holding charge? Why wouldn`t the shorepower fed(or genset fed) batt charger charge all banks? Most can charge 2 or 3 separate banks simultaneously.

 

[Britannia]

If the charger doesn't have two outputs, then the separate starter battery is often charged either by an echo charger or an automated battery combiner that detects voltages and combines when it sees one side or the other being charged (high voltage). You should trace the wires from the starter battery and look for any that could be used for charging.

In the short term you could leave the starter and main battery bank combined while you charge from the shore, remembering to separate them when away from the dock.

Richard

 

[janice142]

In addition to all the good ideas, I'd check each individual cell of the battery.

#1) Get to batt.
#2) Remove caps
#3) Attach ground of your multimeter to appropriate stud
#4) insert Positive lead into batt cells, one at a time
#5) write down voltage
#6) All should be within .1 of each other. If it's .2 difference or above, you've got a cell that's going bad.

If the cell is going bad, buy another battery. Otherwise, find out why you're not charging that remote battery.

Second idea. If you have a cigarette lighter nearby, simply click on some cables (I took an old broken battery charger, whacked off the charger unit, and added a male lighter end -- voila: power!) and it will come up to the level of the other batteries. This isn't charging so much as making the same as the rest of your batteries.

That's how I used to "charge" the battery for Algae.

Good Luck.

 

[AusCan]

I would suggest working out exactly how your charging system is set up. Combining your new house batteries with older start batteries will get you out of trouble, but is not a long term answer. Typically, it just draws down your new batteries the level of your older start batteries.

If your start batteries are only charged by your alternator, it might be worth investing in an echo charger, combiner, or a separate trickle charger for your start battery.
AGM's like to be kept at full charge to get a decent life span.

 

[cardude01]

I would suggest working out exactly how your charging system is set up. Combining your new house batteries with older start batteries will get you out of trouble, but is not a long term answer. Typically, it just draws down your new batteries the level of your older start batteries.

If your start batteries are only charged by your alternator, it might be worth investing in an echo charger, combiner, or a separate trickle charger for your start battery.
AGM's like to be kept at full charge to get a decent life span.

This is what I'm worried about. Killing my new house bank. I thought my charger would charge both banks. Will read up.

Charge light came on for a few minutes then went off. Running about 8 hours today so alternator should charge it.

As usual, flailing around with my DC system. ?

Thanks everyone.

 

[BlueYonder]

What is the voltage taken at the the start battery terminals? If the voltage is OK, it could be something as simple as a fuse or a misplaced battery cable as a result of your house bank change.

What is the brand and model of your battery charger?

 

[cardude01]

Charles 5000

I didn't change any cables to the start battery.

Underway and can't take a reading now.

 

[Larry M]

Does your selector switch go to house, start and or both? On our last boat I ran the house load off of the start battery one night.

 

[ghost]

Always start at the beginning. If you don't already have one, make a schematic for your charging system. You have a group of very well meaning folks giving advice without benefit of knowing how your boats electrical is wired. There is no point in trying to figure out what is not working when we have not even spent the time to understand how your charging system is intended to work, as a system.

In the meanwhile, enjoy your trip. Use a set of jumper cables if you have to and jump the banks together to allow your start batt to charge. All you have to do to enjoy your trip is to play a human battery switch and remember to remove the jumper when not charging to isolate again.

Start your investigation in the morning when the engine bay is cool and you won't feel rushed. The answer will very likely present itself as you document what you have.

P.s. I had the same problem right after I replaced my house bank a year ago. One nice cool morning I found my disconnected charge jumper laying just out of sight.

 

[Codger2]

If you don't already have one, make a schematic for your charging system. You have a group of very well meaning folks giving advice without benefit of knowing how your boats electrical is wired.

Sage advice.

 

[cardude01]

does your selector switch go to house, start and or both? On our last boat i ran the house load off of the start battery one night.

I don't have a separate gen battery.

 

[cardude01]

Here's the schematic

 

[cardude01]

Another strange thing that happened after replacing the house batteries is now my Sidepower thruster joystick will not auto turn off. Light stays on all the time and thruster is active all the time. Sidepower folks said control panel might be bad. ?

Could that be drawing down the engine battery?

Alternator putting out 14.25.

I'm kicking myself now for not replacing that group 27 agm start battery. Guess I'll buy one in Marco or Marathon.

 

[N4712]

Another strange thing that happened after replacing the house batteries is now my Sidepower thruster joystick will not auto turn off. Light stays on all the time and thruster is active all the time. Sidepower folks said control panel might be bad. ?

Could that be drawing down the engine battery?

Alternator putting out 14.25.

I'd get a small victron charger for the engine battery. The charles only charges the house.

 

[cardude01]

Ahhh. I was not aware of that. Ok.

 

[Britannia]

According to your schematic you need to have both the house battery switch and the engine battery switch in the closed position (i.e. on) in order for the shore charger to charge your starter battery. That is an interesting setup and I'm not sure quite why it's done that way.

Here's a quick description of your system:

The starter battery is charged via the "duo charger" which takes its current either from the shore charger or the alternator.

The shore charger will always charge your house bank even when all the battery switches are off.

The alternator will only charge when the battery switches are on (you should always have them on when you are running the engine). It will charge both the house bank and the starter.

The bow thruster and windlass will only operate when the house bank is switched on.

All this assumes that the wiring is as per the schematic and hasn't been modified.

I hope this helps.

Richard
Stillwater
KK54 #5

 

[cardude01]

Thanks for the explanation Richard. I'm not very good at reading those diagrams.

 

[Britannia]

Thanks for the explanation Richard. I'm not very good at reading those diagrams.

No problem. Have you been leaving both battery switches on when connected to shore power? If not that could explain the starter battery not charging.

Richard

 

[cardude01]

No problem. Have you been leaving both battery switches on when connected to shore power? If not that could explain the starter battery not charging.



Richard

Actually I have. I think this start battery is toast. Won't take a charge.

 

[RT Firefly]

Greetings,
Mr. dude. Get a hydrometer. A dead or weak cell will show up immediately.

 

[Britannia]

Actually I have. I think this start battery is toast. Won't take a charge.

There are two 30 amp fuses on either side of the duo charger. You should check those.

Is it not holding charge after a few hours of running the engine?

Richard

 

[Britannia]

Greetings,
Mr. dude. Get a hydrometer. A dead or weak cell will show up immediately.

He indicated that he has AGM batteries.

Richard

 

[LarryM]

I agree with everything Britannia said

If you want a more permanent 'Emergency' solution you might replace the Engine battery switch with a Perko 8603 Battery Selector switch.

Position 1 - the 'Normal' engine Start battery as with the original switch.
Position 2 - the 'Emergency' House battery bank only starting option.
Positon ALL - the Start and House battery banks are 'Combined' - can useful in some situations.
Position OFF - the engine Start battery is disconnected as with the original switch.

The wiring would be as follows:

 

[cardude01]

Yes. AGM.

Ran for 4 hours and stopped for fuel. Dead.

Alternator is putting out 14.2 volts.

Ill check the terminals at the actual battery when I stop.