battery drain

[RETHARP]

i have a 96 crestliner with a 3.0 volvo that i just picked up. the problem that i am having is that i hooked up the battery to the starting side and it started and ran great everything worked. turned off the motor and the next day 12hours the battery was all the way dead. i took the battery to napa and they tested it and said it had less than 1 amp. i bought another battery and hooked it up and checked to make sure nothing was turned on ( blower,pump,radio etc.) the next day the new battery was completely dead. is it possible for the starter or alt to be shorted and cause a drain like this with the key off. please help. thanks, Russ

 

[Bondo]

Re: battery drain

Ayuh,......... Anything is Possible........

Just leave 1 of the Battery connectors Off, til you find the Issue....

You'll have to find a wiring diagram,+ start disconnecting the various systems from the battery circuit til you find where it's drawing power....
That's a Whole lot cheaper than just Throwing Parts at it......

Btw,...... Welcome Aboard to the forums here at iboats....

 

[Haut Medoc]

Re: battery drain

Yup, bilge pump, trim lights, accessories, esp. a cigarette lighter....
Something that is not activated by the key is the culprit.....
It takes quite a bit of draw to kill a fresh battery over night....​

 

[Bt Doctur]

Re: battery drain

Bad alternator will do it too

 

[Don S]

Re: battery drain

Disconnect the large orange wire hooked to the alternator.
Basically, if you have a draw large enough kill a fully charged battery overnight, you must get a pretty good spark when you touch the battery cable to the battery. Remove all the fuses from the fuse panel, disconnect the alternator, disconnect the trim pump (Mercruiser recommend hooking directly to battery.) and seeing if it still sparks. Hopefully it doesn't. Then just put each fuse and connection back one at a time and check to see what causes the spark to come back.

 

[THE BEEF]

Re: battery drain

You can use Beefies way of finding a bad battery.
Buy 2 new ones, go 12 miles out on lake Erie find out there dead, pay $400.00
for a jump,take batteries back and find you have a dead cell.
The joy of boating.
Beef

 

[RETHARP]

Re: battery drain

thanks for the tips. i am trying everything. something that seems strange is that everything has power with the key off. (pump,blower,horn,alt,etc.) is this normal? thanks again for any help. Russ

 

[Bt Doctur]

Re: battery drain

Bilge pumps should be wired direct, that way you dont sink.
with the key off do the gauges operate? If yes, the ign .switch might be bad and always on.

 

[Don S]

Re: battery drain

pumps, blowers, horns, ws wipers, alternators, and electronics all have power when the key is off. The main battery switch (IF you have one) controls the power to all those accesseries. If you don't have a switch, you have to disconnect the battery. They are NOT set up like an ignition switch in a car.
You have something that has gone bad. IF you are NOT good at electrical troubleshooting, it would be a good idea to disconnect the battery/s and take it to a certified marine tech to have it checked out before you find out how long it takes the boat to burn to the water line.

 

[RETHARP]

Re: battery drain

thanks for all the help. after trouble shooting all that i could with the battery hooked up (3 hrs) i noticed that the alt was really hot so i unhooked it and we will see what the night will hold. check it out in the morning. fingers crossed. thanks, Russ

 

[JustJason]

Re: battery drain

if the diodes are bad in the rectifier in the alternator the battery will drain via slow short circuit through the alternater.

 

[BAYLINER185]

Re: battery drain

If the motor isnt running the altanator should not be warm at all.....

Ill bet captJason is right and you found your problem.....Ill keep an eye on this post ro see what the outcome is.....This is a good one to remember myself!

 

[Cptkid570]

Re: battery drain

Let us know what you end up finding out...

 

[JustJason]

Re: battery drain

if you have a DMM with a diode test its pretty simple to test the rectifier. Put the DMM in diode test mode, Put your positive lead on the battery positive and the negative on the alternator housing... check the readout, then reverse the leads. If your showing bias in both directions the 9pack is bad.

 

[rodbolt]

Re: battery drain

I guess troubleshooting with a multimeter would be harder than pokin and hopeing.
myself I would remove a battery lead, hook up my ampmeter in series and start discconecting the various hull/engine circuits until the current draw disapeared, then you have isolated the defective component/wiring.

 

[Jim Graham]

Re: battery drain

The same way I do it Rodbolt only I use a 12v test light , Take one cable loose and make the connection back with the test light. clipping one end to the batt and the other end to the cable .If it lights you have a drain but you can see it. Then disconnect circuits untill the test light goes out.

 

[texanaustinite]

Re: battery drain

I have a similar issue. Only it doesn't drain so fast. My battery will drain in about a week if I don't disconnect it. Waiting to hear what you found out.

 

[RETHARP]

Re: battery drain

problem solved.. it was the alternator. $52 and 1 day to rebuild. thanks for all the help. this site is awsome. Russ

 

[texanaustinite]

Re: battery drain

Thanks for the update Russ. Time to start doing some probing...