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harbormaster
08-23-2002, 10:20 AM
OK when my boat sits for a couple of weeks, the battery goes dead. I know. disconnect battery, put in a battery switch, yada yada, etc.

I would like to know what is drawing it. My first suspect is the radio/cd player memory/clock.

Anyone have a sure fire way to Test for the drain other than disconnecting the radio to see if it does not make the battery go dead?

HyperDonzi
08-23-2002, 10:34 AM
easy thing to do, if you have a nice cd player, it has a clock which never satays set, so this function-less clock sits there telling you it is 12:00 with its nice green light draining your battery. get a toggle switch from any where (the cheapest you can find), then run the power wires to the radio through this then to the radio and mount it wherever it is out of the way (glove box if 18's have one) and when you get out of the boat, flip the switch. battery wont drain [hopefully]. if not the radio, you wasted 3.00$ on a switch. check the nav lights. A bilge pump or blower would be noticeable.

Lil Grizz
08-23-2002, 11:05 AM
My ZX is wired so that the clock memory on the radio bypasses the batt. shut off. The shut off panel actually has a provision for this. I stored the boat through the winter and the clock didnt drain the battery. When I bought my boat the radio did stay backlit even when the panel was switched to off, and that drained my battery in one weekend. I did what HyperBaja said and installed a switch, problem solved.

blackhawk
08-23-2002, 11:25 AM
As Lil Grizz said, the clock "memory" of a stereo should not be draining your battery. My stereo will turn off but the backlight and screensaver will stay on unless you hold the off button down for 3 seconds. Also, I left my anchor light on once and it drained my battery even though my light wasn't plugged in. I thought that was weird. The first thing to do is check to see if this started randomly happening or after you installed something new. Also, check the condition of your battery.

Donzi Blackhawk
08-23-2002, 02:38 PM
Scot,

Simple things first. Make sure everything is turned off, sometimes its that simple. Next, service your battery. Pop the caps and check out the water level, if any are low bring the level up to spec. Fully charge the battery, be careful on how you do this, there are right and wrong ways of doing this so you don't damage your battery.

After you have charged the battery, let it cool for about one hour. Pick up a battery hydrometer from the auto parts store and check each cell for its specific gravity. This test tell you each cells state of charge. Ever here of a dead cell? This test shows you which one, but will also tell you if your battery is capable of not only taking a charge but HOLDING a charge. Also remember that a temperature of 80 degrees F a lead acid battery will self-discharge at a rate of approximately 4% a week.

Make sure the hydrometer shows each cell to be good. Anything less indicates a battery on its way out. After this test have the battery load tested. If it fails the load test, the battery can not be saved at this point. These two tests will take a grand total of five min.

If you want more info, call me 941-371-4012

Bryant

harbormaster
08-23-2002, 04:05 PM
first of all Hyper baja. SSSSHHHHHHH. Watch and listen. You will learn more. I am smart enough to think of installing a switch. If this were the case it would drain your battery in your car in one week. NOT likely the cause.

It is a new Battery. When I disconnect it, it stays charged. What now?

Forrest
08-23-2002, 04:18 PM
One thing that you can do is measure for current flow when everything is shut off. Use a good digital VOM and connect it in series between a battery cable and the battery terminal. Once that you have established that there is current flow, you can now start disconnecting 12v devices, one at a time, until you find the culpret.

Also, this may sound crazy, but make sure that the top our your battery is clean and free from salt and other deposits. Current will actually flow between the two terminals through the crud and discharge the battery.

AVickers
08-23-2002, 05:12 PM
It could be a bad diode in the alternator keeping a winding energized. This would kill a battery fairly quickly...

To check the alternator, you need to measure current flow at the battery terminal with the key off and both with and without the alternator leads connected. If current flows with it connected and disconnected, it's not the alternator -- start looking under a different rock. If current ceases to flow with the alternator disconnected, pull the alternator and have it checked (AutoZone will do it for free -- if you're lucky enough to get a guy at the counter who can hook a non-standard alternator to his machine...)

An alternator rebuild shop can also check it, but there may be a fee.

harbormaster
08-23-2002, 06:36 PM
Thanks.

Some really good info. i would also like to Thank Donzi Engineer for his phonecall and advice.

And Poodle....

"Neighborhood kids playing with the trim button"

You really make me laugh!

Tidbart
08-24-2002, 05:35 PM
LOL, LOL, LOL, LOL!!!

In all seriousness, Poodle hit it on the head.

Good Luck.

Bob

mattyboy
08-24-2002, 07:46 PM
Ok Scot,
you have all the technical answers,now I will give you the real fix,
your battery won't go dead if you use it everyday wink :D :D :D eek!

Matt
You can cancel my membership any time now Mr Harbormaster, Sir wink :p :D

Cuda
08-24-2002, 08:02 PM
I agree with Mattyboy. Nothing like preventative maintainence! :)