Battery Sparks when I hookup neg terminal - Maxum Boat Owners Club

9Ball · 03-28-2013, 12:07 AM

I connected the POS terminal first, then when I connect the NEG I get a little spark. I never noticed this before on my other boats!
Everything is off, Battery switch is off, Shore power is disconected. Do I have a short somewhere?

Todd

biggerseagar · 03-28-2013, 01:23 AM

Todd that is why you always connect the negative last. That spark is going to your ground plate and doing nothing.

I don't know why it is sparks have not gotten that far at battery U but it will hurt nothing as long it is connected last.

Roger

9Ball · 03-28-2013, 02:48 AM

Roger. Thanks I wasn't sure.

Todd

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mcoffey · 03-28-2013, 02:58 AM

Todd, that means you have a draw on the system. It does not matter if you connect + or - last, if there is some sort of draw, it will spark. If the draw is larger than the spark will also be more. Are you sure nothing is wired directly to the battery and bypassing the battery switch? Maybe the stereo or bilge float switch?

paulswagelock · 03-28-2013, 11:33 AM

My 2007 2600 does the same. I have a direct wired load which includes the CO monitor, Stereo memory, and Mercathode system. These are always wired around the battery switch to keep them powered. Bilge pump is as well, but mine is always dry so it is not causing a draw.

ss3964spd · 03-28-2013, 02:07 PM

Exactly as Mc and Paul say, something is "on"; stereo memory, CO monitor, MercCath, a cabin or cockpit light, etc.

9Ball · 03-28-2013, 02:51 PM

I maybe a little overly concerned about this but, I am out on the water at all hours of the night and just don't want to hit the Key to start the Eng and have a dead battery.

I found my Digital Multi-meter. I guess I'll hook it up to the Battery to measure Current, then start pulling Fuses to find out where the draw is coming from.

http://scienceshareware.com/how-to-m...with-a-dmm.htm

I'm thinking something is drawing power, (worried about Draining the Battery) only thing that is hot is the bilge pumps but they aren't running (Land Locked right now on the trailer). Wiring is not one of my better talent's so I am not too proud to ask for advice!

- Bilge pump's are wired to the Float Switch but the boat is bone dry
- refrigerator is OFF
- Battery switch is OFF
- Shore Power is Disconnected
- Mercathode system - N/A
- CO monitor - N/A
- CB Pannel - All CB's are Off
- Radio is only powered when the Battery switch is on (1, 2, or Both)
- All the Switches at the Helm are OFF
- all Lights interior, exterior, running, anchor - OFF
- Trailer Trim

Todd

biggerseagar · 03-28-2013, 03:21 PM

I'll ask my boss at work what is going on for the spark on the negative side to happen...........

Roger

AlwaysSober · 03-28-2013, 03:50 PM

Todd, you probably want to use a test light instead of a multimeter.

9Ball · 03-28-2013, 04:16 PM

If I was just checking for power a light would be better. But I want to see a current draw from the battery drop off as I pull fuses.

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mcoffey · 03-28-2013, 04:29 PM

Todd, you can use a test light for draw as well. Just disconnect the negative cable from battery and connect the test light between the battery and the negative cable. The light will come on and the brightness of it will increase or decrease with load level.
I like using a light as it is easier to see from afar

Are you sure there are no other connections at the battery? I would assume that you have 1 positive and 1 negative cable going from the battery to the switch. You state that the bilge is hot too so there must be those cables connected to the battery as well, are there any others or just those? They could also have connected some wires to the input side of the switch so check there too.
Could there be corrosion inside the switch causing some voltage leak across the Off and On positions?
All it really takes is radio clock/memory draw to cause a spark and if that is all of it, the light will barely be lit when connected between the cable and battery.

So to clarify, disconnect negative cable from battery.
Connect alligator clamp from test light to battery post.
Jam the probe end of the test light into the cable end (normally you can wedge it in the stud hole).
Let there be light :-)

ss3964spd · 03-28-2013, 06:24 PM

There are any number of devices that, even when "off", are still drawing power; the radio is a prime example. The radio will probably have a red/+ (main power), black/-, and yellow/memory. Red/+ (main power) could be wired to a switched source, like the ignition or battery switch, but the yellow is supposed to be wired to an un-switched 12V source. Some amplifiers are also set up to switch to "stand by" mode when the radio is turned off.

Mechanical bilge pump float switches don't draw any power, they just close/complete a circuit. An electronic one might, and a high water alarm also might. I suppose it's possible that a switch might have enough crud built up on it that it might bridge, allowing some current to pass, but nto too likely.

Regardless, pulling the fuses one at a time should find it. I'd start with the radio though.

jrsick · 03-31-2013, 09:32 PM

Do you have anything connected directly to the battery? Are there any small black or red wires connected to the battery terminals? If so, they are drawing a load. Probably nothing to worry about but you may want to fuse them if you're concerned.

9Ball · 04-01-2013, 02:15 PM

There are things connected directly to battery. However they are not drawing any power. (ie: trailer switch is connected to battery but does not draw power till the switch is pushed.)

I hope to do a "draw test" same as you would on a car next weekend. Ill keep everyone posted on how to do this test and ill post pictures as well.

Todd

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