Do you turn off your boat's main battery switch at the end of use everyday?

[skibug]

Based on another thread debating the technical merit of gas octane rating, I am curious about the answers to this question for somewhat similar reasons.

[Horton]

At least on the ProStar the computers are still running after the key switch is turned off. It is not likely you're going to run down your battery overnight but I think it's best practice to turn it off.

[skiinxs]

If it is going to be over a week before the next use, I turn it off (that almost never happens). Otherwise I leave it on. I have never had a battery run down.

[dbutcher]

I don't know, but I suspect that there is another reason (besides battery rundown) that manufacturers spend money to put that switch in their boats. Why is that switch there if not to be used? It costs nothing and takes little time to turn it off/on. Why would you not?

[skibug]

@Horton @dbutcher the reason behind my question was, in fact, a conversation I had with someone at the MC factory. We were not killing the main switch in the new MC because of it new location and relative inconvenience. It is under the removable (pop out) middle observers seat. The factory guy told me it is actually really important to shutdown the main battery switch everyday, because......the main computer is still energized and pulling engine sensor information that feeds into the computations affecting engine performance. As the temps and pressures, etc. swing down, those inputs are constantly being updated, computed, and fed into engine performance algorithms. They told me that I would/should probably see an impact on engine performance over a few day span of only cutting off at the ignition.

 

FWIW....those that have a 2021 MC, we removed the lock down friction post on the front of the seat and the metal "C" holder thingy on the rear of the seat; which makes it much less of a PITA for remove the seat to get to the battery switch.

[LoopSki]

I try to remember after every days use , even after every set. If I forget , battery is really low or dead depending how long. 2017 PS

[Horton]

@LoopSki it sounds like you need a new battery

[ScottScott]

As @Horton mentioned, the prostars have enough battery drain it won't last more than a couple days. Shouldn't drain enough over one night to be a problem, but no more than 1 or 2 nights.

[UWSkier]

The 01 Malibu at my folks' place doesn't have a switch. It often sits for 2-3 weeks at a time. Battery is probably 13 years old. Never had a problem starting. I keep expecting the battery to die someday and it just keeps going strong.

 

My 01 is a garage queen. When it gets home from the lake it goes straight on the on board charger. I don't turn off the power switch.

[Kelvin]

I would use a battery cut-off switch if my boat had one. Generally, my boats get regular enough use that its never a problem. I did have a boat with a cut-off switch. I used it when I thought about it, but not religiously.

[skihacker]

So stupid question, what if the boat is slipped/floating, am I a lunatic because I would prefer the bilge pump has power? The ecm staying energized sounds like a bit of a stupid idea?

[DavidN]

I turn off the main switch on my 2018 SN200 after every use.

Reason is the (in my opinion) stupid bilge pump auto sense feature.

Both bilge pumps would run for a few seconds every minute or so to check for water in the bilge. Kind of useless when the boat is on a lift. And there’s apparently no way to disable that feature.

Downside - I seem to loose some of my ZO settings like the wait time beep, but I can live with that.

On my 2010 Response I never turned off the main switch, as the boat wasn’t using any power when turned off. (Bilge pump had a floating switch that was directly wired to the battery, so even with main power off, the bilge pump would kick on when the floating switch was triggered.)

[Rednucleus]

@skihacker your bilge pump may be wired directly to battery

[The_MS]

If you have a Polk audio in any Nautiques, you need to shut off switch. Amp is always drawing power

[skierjp]

Nautique, I leave the battery cut off switch on and hit the bilge switch so the blue light is not flashing so the bilge pump won’t cycle.

[skierjp]

@DavidN after you hit stop, stop on the keypad you will see the blue light blinking on the bilge pump button. Press the bilge pump button one time and the light will stop blinking and the pumps will not cycle.

[skihacker]

So I'm wondering about this for a couple reasons, our current boat is an 18 prostar, I do turn the switch off mostly because I have heard that the draw is pretty high and right now it's on a hoist. The stereo will run key off switch on but i havent tried the bilge yet. This coming winter the boat is going to be slipped in Florida, I would prefer to leave the bilge powered but doubt it will ever sit longer than a few days. I still find it hard to believe they would build it that way, the acceptable draw on a car is 50 milliamps which is much higher than it was years back but would still take a month or so to kill a good battery. Anyone ever measured it?

[ScottScott]

@skihacker I don't know exactly what the draw is, but after asking our dealer about it. they checked ours, then checked a new boat and they were the same. As mentioned, ours won't make it many days before the voltage drops enough that it won't start. It cranks but doesn't fire.. Worse....it will continue cranking until it either starts, the battery dies, or we scramble to the battery cut off switch and turn off. Not the best design.

[skihacker]

We just racked the boat for the night, the bilge pump does indeed have power with the master shut off,

[Zman]

The only 'downside' of killing the master switch on my 2016 Txi is the radio clock resets. As if I care.

No settings change on ZO.

[oldjeep]

@zman sounds like they didn't run the memory wire direct to battery. That is typically 1 of the 2 wires (bilge is other) that bypasses the switch

[OscawanaSkier]

Malibu dealer told me when they dropped off the boat to always turn off battery switch when you cover the boat. I mostly follow that rule and haven’t had any battery issues.

[LeonL]

The "main" power switch on my 2008 196 may leave something on, I don't know for sure. The three position switch has, "All On", "All On", and "Bilge Only". Its just a small toggle switch, not a switch that can carry starting amps.

@OscawanaSkier what year is your Malibu? There were some Malibu boats in 2017 that spontaneously start on their own. I know, this will get some rabid denials from some Malibu faithful. But as a friend often asked, "Was this you read about, heard about or did you see it yourself?" The answer is, I saw it happen to a boat sitting on a lift at a tournament.