I have a 2017 Sea Ray 210 SPX Has anyone had issues with battery drain? We have had the dealer put 2 brand new batteries and both times they drained completely, and yes battery switch was off, key turned off, all of that. Some suspect the bilge pump m

[wingless]

How long was the unused boat left unattended?

A normal / good battery will self-discharge about 10% per month, higher in warmer temperatures.

It sounds like the boat sits unplugged, w/o the onboard charger working. Is that correct?

Yes, the bilge pump(s) are wired to have power even with the switch off. The pump will make audible noise and on my 2000 380DA the manual / automatic dash rocker switch will illuminate whenever the pump operates.

My boat has those pumps and also the CO detectors wired to be powered before the battery switch.

If I were diagnosing this problem then I would use my AC/DC clamp on current meter on the idle boat to measure / quantify the amount of current being drained by the battery.

Another good step is to measure / log / plot the idle battery voltage versus time. With virtually no load the voltage should remain very constant. Any DC voltage meter (or the boat's voltage meter) is appropriate for these measurements.

[mikemasters1948]

I have a 2018 250 SDX with the same -problem. The dealer cannot get it fixed. Been on the boat 6 times to try. They think it has something to do with the bilge pump but cannot fix it. I'm really only answering so that the forum knows what a crappy boat I've been sold, without any back up from the dealer.

[WaveDancer]

Do you have one battery or two installed? We have a 2021 SPX 210. It has two batteries, and the bilge pump and stereo are connected to one. It sat for four months in the winter with the switch off and I had no problem with it starting up in the spring. I did not test the batteries so the second one may have been partially drained. But having the two batteries sure helps.

[mikemasters1948]

I have two batteries. My boat has gone dead after sitting a couple of weeks. The dealer solution is to run on both batteries.Not recommended by Sea Ray but the dealer cannot find the problem. I'm going to go directly to Sea Ray in hopes of solving the problem.

[WaveDancer]

I did not know that it is Sea Ray's recommendation to not run on both batteries. I always run on both. I switch to one when anchored and have the stereo playing. That way I do not have to worry about running the battery down.

[Bob___Lee_Schom]

I had the same problem with my 2019 230 SLX. I had both batteries replaced 3 times. I finally brought it in to dealer and they monitored it for a few days. What they found was the bilge pump would cycle periodically even if there was no water in bilge. They replaced bilge pump with one that only cycles when certain water level reached. Problem solved.

[ashmoresteve]

I have had the same problem since day 1 of owning it.  Dealer claims I need to plug in the batteries so I have a trickler, keeping the batteries charged.  Only the electrial or house battery drains.  Trying a solar trickler because its a public dock.  Told its due to the GPS on board.  Bad engineering!