Battery discharge through zincs?

I suspect the anode is just a coincidence, and the battery has had it. Test it to be sure

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Triton24 said..
I have a 97Ah battery approx. 4 years old that runs and gets charged from a Yanmar 1GM10. It also gets charged by a 40W solar panel and Phocos charge controller. This setup worked perfectly fine for the last months. The engine always started straight away and the battery never seemed to be weak.
A week ago I put a sacrificial zinc anode on my propeller shaft as I noticed it didn't have one. Yesterday the battery was completely flat. I hand cranked the engine and went motoring for about 3 hours to charge the battery again. It showed 13.4V but still wasn't able to start the engine. Electrical appliances like lamps were very weak.
As the anode was the only thing I changed I suspect it might be the cause. Has anyone experienced a similar problem or knows how I can check? I don't want to buy a new battery and have the same problem again in a week. Any ideas appreciated.

G'day Triton,
Don't you LOVE when your pride and joy starts screwing with your head like this?
Something that wants to go pfft just patiently waits until you are on the boat tinkering with something completely unrelated before deciding to give up the ghost
It would be odd for your anode to have such an effect I would think. You have multiple generation sources, so for a singular failure I would think either battery or if there is a singular charge regulator (doubtful come to think of it, solar and diesel prob have their own)
You could check to make sure your system is charging by a simple volt meter across the battery with the diesel running, should show +13V.
If the battery is not sealed check the water levels, you might have a dry cell?
Cheers!
SB

Edit: Recently we started a diesel car with one of those dinky little lithium battery packs that look like an oversized phone charger, it blew me away how much grunt these things have. I keep thinking it would be a cool thing to get one for the boat for dead battery issues. Only any good I suppose if your charging system is OK to get you home of course!

Hi Triton
Take a step back and remove the zinc.
If the problem is gone that is the cause.

gary

dumb question, but how or where did you put the anode on? I'm guessing it was a collar type around the propshaft, and you had the boat on the slip?. if that was the case, and all that was done, I think the above responses would be on the money, probably not related.

And Shaggies idea, I bought one of these lithium jump starters, thinking it would be a great idea for the boat. Have used it around the garage a few times, and it's virtually idiotproof, you can reverse polarity it, even short the terminals together whilst its on by accident and no sparkies. Downsides:charges by usb or a 12V socket (but if your battery's already flat???)

I also envisaged I could use it as a little battery bank, to transport ejuice if you like, a jerry can for voltage. Charge it at home, and connect it to the boat batteries when they are low, especially during winter when the solar isnt doing much. The potential voltage difference between the charged jumpstarter and the 'flatter' boat batteries would effectively 'charge' or top them up right, given a bit of time?
No, not in practice. If you are using it connected to crank your diesel over, it would work providing a power source boost, but not in the trickle example described above, the unit doesn't activate or effectively switch on.
Could just be me, quite likely, but something to know maybe.