Batteries Draining Question ?
 

I got a problem and the mechanic is either an idiot or I am.........Sunday morning.........went to take the boat out tried to start the boat........dead batteries........BOTH OF THEM.........I'm baffled at this.......both dead at the same time........hard to believe...........try to jump them from a jump box but not enough juice in the jump box I guess. It wasn't fully charged..........I decied to pull the batteries out and take a look. They were the old style that you add water to. So I pop the caps off and see that the water is very very low in most of the cells.......I fill it.........hook it to a battery charger to see if the water bubbles or if the cells were dead........most of the cells were shot..........checked the other battery and did the bubble test.........same thing........dead. GREAT........so I think I found the problem.....the batteries were old so I figured they saw their better days and needed to be replaced.
I go to the autoparts and buy 2 brand new delco's.......sealed with the eye on the them. Get them back to the house and install. Boat fires right up and off I go.

Monday I try to go out but it turns out I shredded an impeller in my shallow canal (another story) and the boat was overheating back to the dock I go.......call the mechanic he comes out Tuesday and replaced the impeller. Didn't go out Tues. it was late.

Wed. I decide to go out and make sure everythings fine with the engine and it doesn't overheat. I did notice upon starting it ...it kinda turned over slower than normal but didn't pay much attention to it at the time. Went out for a little run and engines were fine.....engine temp was normal again. Great, impellers fixed, batteries problem fixed were looking good.

Thursday, I'm blowing out my well to try and get rid of loose dirt and deepen it a bit........the boat is docked along my seawall. I thought about the slow start from the last time I went out and decide to start it up for good measure. SURE ENOUGH........batteries are dead.........HOLY SHHIT! I can't believe this. I call the dealership they say someone will be out TODAY!

Keep in mind......I just bought this boat in July and have had nothing but problem.......see post (big big problems in Fountain Section). Just had an engine replaced and none of these battery issues started until after this install.

Back to the story.......genius mechanic comes out.....supposedly tests EVERYTHING........he even took the boat out to run it........why I have no idea.......don't think that was necessary but what do I know.......he said he took out the stereo and reset it...(whatever that does)........says nothing is draining off the batteries and that I should keep the battery switches off EVERYTIME the boat is not in use. And that's it........he says there's no problem.......the whole time I've had the boat prior to the engine install the switches were ALWAYS ON and I never killed the OLD SHHITTY BATTERIES..........I FIND THIS VERY HARD TO BELIEVE! IT'S IMPOSSIBLE IN MY MIND! THERE IS NO WAY IN HELL LEAVING THE BATTERY SWITCHES IN THE ON POSITION WITH EVERYTHING IN THE BOAT OFF CAN FLATEN TWO BRAND NEW BATTERIES......AM I AN IDIOT OR IS HE ?

Any suggestions or diagnosis are greatly appreciated!
Thanks in advance!

Re: Batteries Draining Question ?
 

Niether..

It sounds like something is still drawing power when everything is turned off. Something that when you turn off the battery switch, then it turns off also.
If that is the case then turning off the batteries will solve the issue, until you find what is draining the batteries.

You can find this by using a amp meter. Turn every thing off, then test for amps at the battery with the switch on and then with the switch off. Any change in amps then you need to take the meter and test every lead on the electrical box.

It only takes a couple minutes to do this.

Another possiblility is your alternator is over charging your batteries. (which is probably why he took it for a spin).

I'd check the bilge pump switches, i've seen them cause this kind of problem.

Re: Batteries Draining Question ?
 

I had a bilge float switch break off and lay on it's side in the on position. Like wild said, put the volt/amp meter inline and see if anything is drawing current.....

Re: Batteries Draining Question ?
 

These are all good responses but if you don't find anything, turn the battery switch off. Embarrassing to say, but I've had my boat for 18 years and have had a mysterious short/drain that I've never been able to find, even with all the tests- it comes and goes. A friend with a 3 year old Powerquest has had the same problem and by turning off the switch we've both not had any problems. Good luck and post if you do find something.

Re: Batteries Draining Question ?
 

When that happened could you hear the bilge running ? I don't hear anything running and both bilge pumps work fine when I turn them on but you can definitely hear if they are running.

I will find out in the morning if turning the battery switches off turns off the source of the problem.....if the boat is dead again in the morning then there is definitely something else going on. I manager of the service department is coming out in the morning to test the alternator.......he says the diodes in the alternator could be bad and if that's the case they will charge the batteries but they will also pull juice from them when the engines are off.......first I've heard of this....more to follow in the morning.

Re: Batteries Draining Question ?
 

My only problem with this would be........I would be scared everytime I went out that my batteries would die and I'd be stuck out on the lake somewhere. Plus I would be really scared to stop and use the stereo and other accessories. That's not my idea of fun!

Re: Batteries Draining Question ?
 

If your Mercothode (anti corrosion) systems are shorting out can they drain your battery that fast? Not having your bildge pump working while the boat is docked is not a good plan.

Mike

Re: Batteries Draining Question ?
 

All you need is one good rain with the battery off and you are going to fill that bilge. You'll be looking at starters and all other fun goodies.

Are they starting batteries or deep cycle. The bilge pump alone will kill a starting battery in a few days. If you put it on a lift, pull the plug and then shut off the battery, but make sure its up for the tides

Re: Batteries Draining Question ?
 

There's a lot of good advice here. On my boat, turning off the batteries does not turn everything off as noted above. Bilge pump and other items are still enabled. I ran the 'house' battery dead this winter in heated storage by leaving the volt meter switch on that reads the voltage on the batteries. Everything else was turned off. Assuming the charging system is ok, I'd measure the draw on each battery with everything off and see what you have. I don't know how your boat is wired but with mine I can start each motor with its own battery or drawing from both or start each motor with just one good battery. The port battery is the house battery to run the stereo, etc. That way the stereo could run the port battery dead and I could start both motors with one good battery. You must have a pretty good draw to kill both batteries so quick. Let us know how you make out.

Re: Batteries Draining Question ?
 

Someone already mentioned the Mercathode System. I bought a new boat that would kill a battery in a couple of days. Put in a new battery and turned off the battery switch, couple of days later dead. Turned out the Mercathode system was faulty and was wired direct to the battery by the manufacturer (which is correct in a saltwater enviroment). Steve

Re: Batteries Draining Question ?
 

Turning off my battery switch does not turn off the bilge pump, blower or stereo either. They are directly wired to battery 1 and , apparently, none of the problem as they have not drained any battery. You may have to check what is directly sent to the battery(ies) and what goes through the switch.

Re: Batteries Draining Question ?
 

A blown diode in my alternator would drain my battery. It still charged but when the boat was not in use, it would slowly drain the battery. I replaced alternator and problem was solved.
Alternator is a four wire, 55 Amp Mando .

Re: Batteries Draining Question ?
 

I have a charging system on my boat. When ever it's parked I plug it in for a few days and and plug it for a few days. It's an automatic charger but I still like to cycle it on and off myself. I usually plug it in a couple of days before I go out. No big deal, at least I have the piece of mind that when I go to use my boat my batteries will be fully charged. I have four yellow top optimas BTW and I know that Merc 55 or 60 amp alternator can not charge them after playing the stereo all day in a 20 minute ride back to the ramp. Most GM alternators don't charge at idle so when you idle through a no wake zone or you are waiting for the trailer at the ramp you aren't recharging your batteries.

Re: Batteries Draining Question ?
 

couple things........my bilge pumps still run with the battery switches off......they are the only thing that runs that I know of too........whatever is draining my batteries is stopping when the switches are off. I had the switches off for a couple days the batteries were fine. I don't know if shutting off the switches would stop the Alternators from draining them if in fact they are the culprit. It rained Saturday so the mechanic didn't come out. Might be out today yet.........we'll see.

Re: Batteries Draining Question ?
 

Do you have a VHF in the boat ? If you do here is an easy way to check the diodes. start the engines and let them idle. have someone else listen to another VHF close by. If they hear a whinning sound when you key up you have a bad diode in the alternantor, when the diode fails it alows electrical feedack that wil produce the whinning sound on the radio.

Re: Batteries Draining Question ?
 

Hillbilly,
Good Info!

Re: Batteries Draining Question ?
 

I had an alternator on my Fountain that would drain the batteries pretty quick. Had it rebuilt for allot less than new and works fine . I still shut my batteries off when not in use but if there is a draw, something is wrong. I like knowing everything is working correctly.

With everything turned off, disconnect the ground wire on your battery. Now attach a multimeter between the battery ground terminal and the NEG battery cable you just removed. You should only indicate approximately 2-3 volts. Readings at 10+ volts indicate an electrical drain. With the meter still connected, go to your accessory fuse box and remove one fuse at a time - when the voltage drops on the multimeter then you located the source of the drain - Don