Starbard bank dead

[Byron]

Had the boat pulled and blocked on 10/11/23. The boat sat between 10/11/23 --10/19/23 between those dates I have been to the boat numerous times opening and closing the engine hatch cleaning the engine room. The boat was never plugged in between those dates. 10/19/23 the marina showed up and winterized the engines and changed the oils. I went to the boat this morning 10/22/23 and turned on the battery switches. Port side was fine but starboard side was dead as I couldn't open the hatch. Plugged in the boat, waited ten minutes and the hatch worked. Evidently the starboard bank was dead. Load tested all four batteries, O.K. All batteries replaced 6/23. I would think that the marina running the engines for some time on 10/19 would have charged the batteries enough for me to open the hatches on 10/22. I checked the bilge pumps and the CO's are disconnected. Also, the Port batteries are dual purpose and the Starboard are start batteries. Right now the boat in on charge. I will stop by tomorrow morning and unplug it, wait a couple days and see what happens. Any thoughts on this.

 

[Lazy Daze]

Starboard doubles as your house batteries? The obvious reason is that someone left something on between the last time you were there and the 22nd. Other than that, you have to start looking for a bad circuit causing a parasitic draw.

 

[Byron]

Im positive both battery switches were off at all times except when I opened the hatch and when they winterized the boat. Is there any way I can check for draw at the batteries whith the switches off? Bear with me as I'm not the best with electrical issues. However I do have a digital volt meter and a lot of patience. Thanks for the help.

 

[keokie]

Oftentimes, the draw is the smart charger which is typically wired directly to the batteries.

 

[Byron]

I changed the charger to a ProNautic 12-30 last year. It is directly wired to the batteries. So what your saying is that if I don't have the boat plugged in and the switches off the charger will draw current and eventually lower the voltage in the batteries.

 

[Lazy Daze]

I changed the charger to a ProNautic 12-30 last year. It is directly wired to the batteries. So what your saying is that if I don't have the boat plugged in and the switches off the charger will draw current and eventually lower the voltage in the batteries.

Only if there's an issue with the charger.

You could do an "amp draw test" or "parasitic draw test". Google can give you lot's of info on this, but the jist of it is that you remove the negative cable on a battery (in the case of parralel batteries, use the battery that has the initial negative lead on it) and put your meter (start at 10a, move down to 2a if needed) between the (removed) negative lead and the neg battery post. You should read something in the low ma range if everything is OK. If not, remove any accessories (charger, for example) that are wired direct and do it again. Process of elimination (and removing fuses/turning off individual breakers) will find the offending circuit (if there is one, that is).

 

[wineknot]

Even with the battery switches off there are probably things that could have been left switched on with power. On my old boat (not a Sea Ray), the battery switches killed power to the engines but the helm and cabin below still had power. I had a separate breaker for helm and the DC main breaker on the cabin panel was independent of battery switches. The blowers could have been left on and killed the battery. A friend had that happen when the marina left his blowers on after they pulled his boat out. Are you sure all the helm switches and blowers were off when you got there on 10/22?

 

[Byron]

Thank you for all the easy to understand feed back. Boat is out for the winter. I fully charged, tested and then disconnected them. I'll look into the parasitic draw test at a later date.

 

[Jimmy Buoy]

Bilge pumps are often direct wired to the batteries (will operate even with the switches off). I had a shower sump box that I discovered drawing 12vt power. With all systems off and no distracting noise just before storing the boat, a faint whirring could be heard below the floor. Closer inspection revealed the shower sump pump running at a slow pace even though the box was empty of fluid. The switch was in the down position. When raised up, the pump ran at full speed. After lowering the switch back down, the pump stopped. Within a few minutes the pump was running at a slow pace again. Jiggling the switch up and down stopped the pump, only to have it partially engage a few minutes later. Floating pump switches can go bad apparently. First time for this act. Just an idea to check out...

 

[Byron]

Thanks I will carefully check them all.

 

[carterchapman]

Floating pump switches can go bad apparently.

Since they took the mercury out of the float switches they are a PITA...