Battery Isolation

[mebscdr]

Recently purchased used 2014 Sunchaser 8520 Cruise with Merc 115 4-stroke. When connecting the leads to the single battery, there was a spark on the positive side. So, I looked for a battery isolation switch and could not find one. (i also could not find a circuit breaker panel)
Is it possible, that the boat is designed without a battery isolation switch? If so, does that mean that the ignition key switch serves as an isolator? If so, it is not working since the sparking happens even when there is no key in the ignition switch.
Thanks in advance for your thoughts.

 

[dingbat]

Recently purchased used 2014 Sunchaser 8520 Cruise with Merc 115 4-stroke. When connecting the leads to the single battery, there was a spark on the positive side. So, I looked for a battery isolation switch and could not find one. (i also could not find a circuit breaker panel)
Is it possible, that the boat is designed without a battery isolation switch? If so, does that mean that the ignition key switch serves as an isolator? If so, it is not working since the sparking happens even when there is no key in the ignition switch.
Thanks in advance for your thoughts.

I assume your talking about a 1/2/Both battery switch since an actual battery isolator is typically an aftermarket addition.

Sparking simply means something, somewhere in the boat is using power. Things like bilge pumps, chart plotters, etc. typically don't go thru the key switch for obvious reasons

 

[gm280]

Like dingbat stated, something on that boat is using power. And if you don't locate that power usage, you will go to the lake one day and have a DEAD battery! There really shouldn't be anything making the battery spark on a boat sitting on a trailer. So you need to trace that down and fix it, OR hope between your home and the lake, it still has enough power to crank the engine when you get there. JMHO

 

[mebscdr]

Pontoon boat. no bilge pumps, no chart plotter, no marine radio, etc. Besides the motor, the only other electronic/electrical is am/fm radio, nav/anchor lights, a cigarette lighter, gauges.

 

[mebscdr]

Dead battery was exactly what happened, on the second time trying to take it out.

 

[dingbat]

Dead battery was exactly what happened, on the second time trying to take it out.

Outboards have a limited capacity to charge a battery. You must recharge the battery between uses.

Although usage is very small, most radios/CD player, etc are constantly powered to maintain the presets. Check to see if this isn't causing your spark

 

[sam am I]

Dead battery was exactly what happened, on the second time trying to take it out.

Alternator bad most likely.........Think those run standard type alt's, probably shorted/leaky rectifier/s. Unplug/disconnect all the wires to the alt, recheck for EXCESSIVE sparking when re-connecting up good battery. Sparking gone? Alt. bad causing rapid battery discharge/dead batt, hence the spanking, errrrr rather "sparking".

 

[mike_i]

If you don't have a circuit breaker panel how are the lights and radio connected to power? I would disconnect the pos cable disconnect the radio then reconnect the pos cable to see if it still sparks. I'm guessing the only thing that may be drawing current is the radio. Would you happen to have a voltmeter? If so you can connect it in series with the pos cable and get an idea on the current draw. What gauges do you have? Are any "on" like a battery gauge? It would be a good idea to install a battery switch regardless of the outcome, it's nice to know everything is turned off when the boat isn't in use.

 

[KD4UPL]

Radio is probably drawing power. Install a toggle switch in it's power lead. Problem solved.