Everything seemed fine before the boat sat in dry dock for a month. When I picked it up, the engine started right up as normal, but my Raymarine Dragonfly 7 (not particularly advanced. It's a fish finder) and the oem depth sounder would not turn on. After motoring for 10 min, they'd turn on sporadically for a few seconds then turn off. I ended up flipping the breaker and not mess with them for that trip. Subsequent trips seemed fine (batteries on the tender when not sailing), but very occasionally I'll look up and the Dragonfly will be off. It also seems that it will turn off somewhat reliably after cranking the engine. It may even take a coule tries to boot- like the power is bobbling.
I have two, new-looking, group 31, AGM, "Marine Dual Purpose" batteries run in parallel. There's nothing at all fancy about the setup. Only one bank and no house/engine separator.
Question 1- What do you think the issue is here?
Question 2- What size battery should I dedicate to the engine should I install a 2 bank system? (Yanmar 2GMF, 2 cyl, 586cc)
I have two, new-looking, group 31, AGM, "Marine Dual Purpose" batteries run in parallel. There's nothing at all fancy about the setup. Only one bank and no house/engine separator.
Question 1- What do you think the issue is here?
Question 2- What size battery should I dedicate to the engine should I install a 2 bank system? (Yanmar 2GMF, 2 cyl, 586cc)