Battery drain issue

[Augoose]

I've got a significant drain issue and I'm trying to locate it - any suggestions? Over the course of one week, my new battery is totally dead. In my jeep I'd just hook up a test light and begin pulling fuses until the light goes out - but my test light is broken and I can't seem to find a fuse box anyway.

I'm planning on disconnecting the positive lead to the battery, clipping the red lead on the meter to the positive cable and then clipping the black lead to the battery ground in order to check for voltage drain. My question is how can I efficiently disconnect items to check to see if they are causing a drain without a fuse box?

What are some common culprits of battery drain? My blower wasn't on, my bilge has a float switch so it shouldn't have been on as the boat was on a trailer and my lights were turned off. My radio wasn't on either and that's about it as far as external electronic devices.

I just recalled this - my float switch allows 11.3 volts to the bilge pump all the time and then when the float is tripped, the voltage increases to 12.3 and the bilge turns on. When there is 11.3 volts, the bilge doesn't run. I would have thought that when the float switch isn't tripped, there should be zero volts to the bilge - could this be my problem? I called West Marine and they assured me that 11.3 volts to the bilge "when it's off" is normal.


Mercruiser 4.3 w/ Alpha I
1989 Caravelle ES 202

thanks

 

[lakeerieboater26]

Re: Battery drain issue

I just had an issue with my battery always draining and it was my radio. even when it was turned off it was drawing power. I just disconnected it.

 

[Augoose]

Re: Battery drain issue

I just had an issue with my battery always draining and it was my radio. even when it was turned off it was drawing power. I just disconnected it.

I was thinking of the radio. Its as old as dirt anyway so I might disconnect it and test it.
Thanks for the suggestion

 

[a70eliminator]

Re: Battery drain issue

"I'm planning on disconnecting the positive lead to the battery, clipping the red lead on the meter to the positive cable and then clipping the black lead to the battery ground in order to check for voltage drain. My question is how can I efficiently disconnect items to check to see if they are causing a drain without a fuse box?"

I'm having trouble figuring out how that will work.
Would that show current draw in DC miliamps?

 

[Kevinmcm]

Re: Battery drain issue

"I'm planning on disconnecting the positive lead to the battery, clipping the red lead on the meter to the positive cable and then clipping the black lead to the battery ground in order to check for voltage drain. My question is how can I efficiently disconnect items to check to see if they are causing a drain without a fuse box?"

I'm having trouble figuring out how that will work.
Would that show current draw in DC miliamps?

NO! the proper way to check current draw with a meter is to unhook positive lead, hook red lead off meter to cable and black lead to the positive battery post (ensure meter reads DC amps). Then begin unhooking things from the circuit and when the load is unhooked, your meter will show a loss of amperage.

 

[a70eliminator]

Re: Battery drain issue

That sounds better! yep yep..

 

[Augoose]

Re: Battery drain issue

...hook red lead off meter to cable and black lead to the positive battery post (ensure meter reads DC amps)...

Thanks for the clarification. Phew! Narrowly avoided a boat sucking black worm hole!

Now to make a list of electrical components and figure out the most effective way to temporarily remove the power source to check for the drain.

Thanks again for the clarification.

 

[Lion hunter]

Re: Battery drain issue

Have you verified 1st that it's charging before looking for a drain? Put a multimeter on the battery while running to see if voltage is above 12v. After that I would check for drain.

 

[hungupthespikes]

Re: Battery drain issue

Inductive Ammeter

http://www.stuttgartperformanceengineering.com/inductiveammater.html

sometimes these work the best. no wires to unhook.

 

[bruceb58]

Re: Battery drain issue

Inductive Ammeter

http://www.stuttgartperformanceengineering.com/inductiveammater.html

sometimes these work the best. no wires to unhook.

Not sensitive enough. Just use a multimeter ammeter.

 

[Silvertip]

Re: Battery drain issue

The float switch should not allow ANY voltage to the pump at any time except when it is triggered by rising water. You have already found the culprit. float switches are either ON or OFF. There is no in-between.

 

[Augoose]

Re: Battery drain issue

Lionhunter - yes, I believe it is charging. I put the battery on a trickle charger which charged it up enough to start then ran it for an entire day. Voltmeter showed a full charge the rest of the day.

Bubba1235 - The boat is a 1989 Caravelle ES 202 with Mercruiser 4.3 w/ Alpha I. I looked all over and under the dash and couldn't find any master fuse box.

The float switch should not allow ANY voltage to the pump at any time except when it is triggered by rising water. You have already found the culprit. float switches are either ON or OFF. There is no in-between.

That makes sense to me. I couldn't figure out why the pump should get 11.3 volts when the system should be off - the West Marine guy was causing me to second guess logic.

I'll rewire/replace the float and see if that solves the issue.

Thanks to all.

 

[Ocean Airbrush]

Re: Battery drain issue

If your float switch is allowing voltage through then you need to replace the switch and the pump. If the pump is receiving current that is enough to energize the coils but not enough to run, then those coils simply heat up and dissipate that energy as heat energy. This causes premature mortor burnout. Of course being as it is in a boat this will manifest its self at the worst and most crucial moment of pump operation.

Pumps are cheap, don;t take chances.

 

[Augoose]

Re: Battery drain issue

Well I think I fixed the issue. I removed the float switch and just wired 12v switched directly to the pump until I get a new float. The boat sat over night and was reading over 12v the next morning, so I think I'm good to go. When its not in use it sits on a trailer w/ the drain plug out.

Second question - my brand new interstate battery was completely drained twice in the course of fixing this issue. Do I need to go ahead and get a new one? Its a marine starting battery - I don't recall the cranking amps off the top of my head - around 800 or so I think.

Thanks!