What is Draining My Battery?

[LippCJ7]

Re: What is Draining My Battery?

Jcornell,

Ok so by hooking up the jumpbox directly to the battery you are telling me that the ground between the engine and the battery should be fine, you are not removing it from the system when jump starting it.

You are measuring battery voltage when you go from post to post should be 14(plus or minus) when the boat is running and 12-13 when not running. positive DVM probe to positive battery post and negative DVM probe to negative battery post, again do not measure through the terminal on the battery posts since they could be part of the problem go directly to the post.

While you are at it switch your dvm to ohms, measure on the >100 ohms scale(just generalizing here not knowing what you have or are going to get could be the 20 ohms scale) and measure from the negative battery post to the engine block, should be zero but who knows what you will see, this is called resistance and in the electrical system resistance is very bad, more is bad, less is good. You can use this across the battery terminals as well, measure from the battery post to the next clean connection you can find, you are measuring the resistance through that section of line including the terminal, you can do this on positive and negative.

 

[LippCJ7]

Re: What is Draining My Battery?

I never trust the battery terminals only the posts, too many times I have had friends come and tell me they have a bad line only to find out they only have a bad terminal, remove that from the equation, typically I test the terminals first then the ground to chassis or in a boats case ground to motor, make sure you are getting a good connection on both ends DVM's can be super accurate, lick your fingers put the DVM on ohms and test the resistance of your body one probe in each hand(IT DOESN'T HURT), your wife may be off the scale I know mine is...

Once you verify a good ground you can use that point for further up the system

when checking resistance(Ohms) 0 is perfect, 5 is horrible and becoming a serious voltage drop

Voltage on your boat or car is 12 Volts DC, 14VDC is fine and an indication your alternator is charging, but when your alternator senses that your battery is fully charged it will turn itself off and your battery should settle at 12-13VDC

Don't get me started with Volts AC only crazy people mess with Volts AC... but there are no AC volts in this case.

Also if you are married take your wedding ring off and any other jewelry off your hands don't ask just do it!!

 

[LippCJ7]

Re: What is Draining My Battery?

Also I'm off all day so just bring it over...


LOL I KILL MYSELF!!
Bring Corona!! LOL

 

[ssobol]

Re: What is Draining My Battery?

You say the battery is dead. Is that the case (i.e. are all the other electrics/lights dead) or does the motor just not turn over. If you have a low battery you should have no lights or the lights will go very dim when you hit the starter.

It is possible to have a bad starter motor or solenoid that only works when there it a lot of voltage (full battery). Unless the battery is completely flat you should at least hear the starter solenoid click when you try to start with a low battery.

I had a car once that would act like it had a low battery. You'd turn the key and any lights that were on would dim like you had a low battery. There would be no click or cranking. When this happened I could get the engine to start by banging on the starter motor once or twice with a piece of wood. I carried a baseball bat in the trunk for just this purpose. Inboard engines are essentially car engines. It is possible this is your problem.

In a car it takes 20-30 minutes to recharge from a start on a good battery (at idle). If you have a weak battery it will take longer (battery can't accept the charge as fast). A good battery will have enough energy for a few starts. Say you only have enough charge for one start. You start it up, let it run for 5 minutes, and say everything is ok. Well you just blew your one chance because you didn't let it run long enough for the battery to recover.

Ideally you should have an ammeter installed. You can watch the meter and tell when the battery has stopped charging after a start before you turn the engine off.

 

[Vegas Naturist]

Re: What is Draining My Battery?

Vegas N, this statement from you is not correct.

Don't want to hijack or side track the thread, so we'll have to have this discussion another time.

John

 

[Chris1956]

Re: What is Draining My Battery?

Hey John, Maclin is correct. If you don't agree, start a new thread and we can explain.

 

[jcornell26]

Re: What is Draining My Battery?

You say the battery is dead. Is that the case (i.e. are all the other electrics/lights dead) or does the motor just not turn over. If you have a low battery you should have no lights or the lights will go very dim when you hit the starter.

All electronics work when this happens. Radio/Trim/Gauges...etc. It just doesnt turn over.

It is possible to have a bad starter motor or solenoid that only works when there it a lot of voltage (full battery). Unless the battery is completely flat you should at least hear the starter solenoid click when you try to start with a low battery.

Check out this thread I posted a few weeks before I got that new battery a month ago I described in the OP. That purple wire was recently hooked up as you can see in the before and after pics. What is that purple wire for?

http://forums.iboats.com/showthread.php?t=548884

 

[LippCJ7]

Re: What is Draining My Battery?

jcornell, does your negative battery wire still get very hot when this happens? or did you fix this problem?

If you have not fixed this I want you to take one end off and measure the resistance of this cable, I want you to do this first thing, if it measures 0 no problem if it measures more then a couple ohms I want you to replace it before moving on, you can find a direct replacement at any auto parts store except I want you to look for one that is bigger then the one you have(bigger wire I would look for something close to 2 gauge), also if you can take a picture of the top of your battery I want to see the condition of your connections at the battery, if the pictures in your other post are any indication I wouldn't waste time swapping batteries, your battery is fine. Get a DVM and lets get to finding the solution to your problem.

 

[jcornell26]

Re: What is Draining My Battery?

Lipp - After cleaning off all the corrosion that solved the problem of the negative wire heating up.

What about that purple wire?

 

[LippCJ7]

Re: What is Draining My Battery?

I don't know what it is for you would have to trace it but I dont think it can hurt anything, problem is we need to know what it does, and you we need a DVM for that, got one yet? LOL Point is if its a ground and it is hooked to a hot point then its no longer called a wire its called a fuse and it would have burned up, you can figure things out with a DVM that eliminate the need for a schematic which you don't have and probably cant find anyway, wires are typically in loom or some other type of wire management, but you can almost always find the ends so then you simply put your DVM on Ohms and hook both side of the wire(both sides of the wire need to be disconnected) and verify that is or is not your wire.

Even though you cleaned up both ends of the wire I would like to know the resistance across the wire, corrosion can follow the copper wire up under the PVC insulation of the wire and create an issue, we know you have a corrosion problem from your previous pics so its not a longshot to assume that you likely have a ground issue in your boat, you have the proper size wires unfortunately its possible that the corrosion has damaged the wire to a point where your electrical system no longer has the ability to pass enough amps to fire the motor, again I am not saying this is the problem but we need to verify the integrity of the wire itself and the connections which look good now that you have cleaned them I want to see the numbers, they will tell us the whole story.

 

[jcornell26]

Re: What is Draining My Battery?

Gotcha. No DVM yet...I am still at work. I am going to pick one up on my way home though.

 

[LippCJ7]

Re: What is Draining My Battery?

Lowes Home Depot they all have them, you don't need to go crazy and buy one like mine, I actually need the other features, Ohms DC Volts AC Volts Milliamps, most decent DVM's are good to about 10 Amps as an Amp Meter outside of that your talking a good amount of money but if your careful you can still use it, I do all the time my Fluke DVM is about $200 but I have a much better knowledge of electricity, soon you will too.

 

[jcornell26]

Re: What is Draining My Battery?

There has been a lot of suggestions in the last 2 pages. I have the day off tomorrow so I am going to work on this. What is the first couple things I need to check? Battery posts right? What else?

 

[LippCJ7]

Re: What is Draining My Battery?

ok the first thing I do is check my battery connections and then grounds

Put your DVM on 20 ohm scale, take one probe and press firmly into the post, take the other probe and put it on the next connection so if I were to do the negative or the ground side I would press one probe firmly into the negative battery post and the other probe to a clean metal surface on the motor close to where the ground wire is attached, this should read zero ohms, anything more and we need to clean it up or replace the wire, go to the next wire doesn't matter which but do everything you can to get resistance to zero on every wire you can.

Resistance adds up 1 ohm on one wire that is attached to another wire with another ohm in it and you have two ohms etc etc, knowing this, you have one ground wire that goes to your helm and most or all the grounds in the helm go to that wire so you can see where this can be an issue, another problem is that wires have a load limit, manufacturers build a boat to the load they have and rarely oversize wire for future expansion, so we may have to replace the stock wire for a larger wire, some would say that you can just add a wire and this is not a good idea in my opinion for a couple reasons that will be way over your head, but lets say you used the stock wiring when you added a big stereo system, but you had a marginal main ground to your helm, since your ground is marginal the extra voltage will try to find another route to ground, when this happens all kinds of things get crazy, heat can also play a factor in a marginal wires ability to pass a load....uhoh sounds like this could be similar to your issue doesn't it? so for right now lets get you trained on how to use a DVM and then you can check whatever you want.


one of the things you may see is when you are reading voltage say on your fuse block, you have already tested your grounds and your good there so you have your negative probe on a known good ground, your DVM is on the >100VDC setting and your simply checking voltage on each specific fuse, you see 12.5 VDC on fuse 1,2,3,4,6,7 but on fuse 5 you have 12 volts, what gives? pretty simple you have a resistive connection and you have a voltage drop, if you measure resistance(Ohms) you will find a couple Ohms resistance on that fuse and it needs to be cleaned or replaced. do you remember when we had glass barrel fuses before we had blade fuses? the reason why they changed design is pretty simple, the fuse was made from a few parts assembled to create a fuse, two metal ends a glass barrel and the fuse inside which is soldered to the metal ends but there is a reason why these can be bad, say you have a 15 amp fuse and it will not pass voltage once it gets hot, the problem most likely is that you are drawing 14.8 amps through the fuse, it melts a little bit of solder and loses connection but after a little bit the solder cools and the fuse regains a decent connection, this can go on and on, it will get worse over time until it finally fails but in the meantime the only way to find it is to measure resistance through the fuse and you will find a few ohms through an otherwise good looking fuse, seen this a bunch on difficult projects, of course the easy answer is to just put a bigger fuse in but you need to properly fuse a circuit but you are not the original owner of the boat how do you know the PO didn't do something silly?

anyway get to playing with it, don't touch the metal ends of the probes it isn't dangerous but it will change your readings, you can put your positive probe on your negative battery and read voltages backwards but your DVM will put a + in front of your reading telling you its reading a positive ground and you will most likely never see a vehicle with a positive ground system, it will not hurt a thing, the only thing you can do to hurt your DVM is read to many Amps and pop the fuse, do this more then a few times and you will break your DVM other wise they are pretty bulletproof. If your reading is outside of the setting limits you are set on it will blink or do something weird so don't panic its ok its just telling you it needs a higher setting.

Sometimes I need to know I have a good ground to the helm but I do not have enough lead, the easy way to do this is to purchase a 10' section of 18 gauge wire and a terminal or a couple alligator clips(any decent auto parts store) and make an extension, make sure you test it for resistance before you use it!! I always touch my leads together on Ohms setting just to make sure I have good leads also 0 ohms is a beautiful thing.

 

[rbh]

Re: What is Draining My Battery?

Hey lipp, did you guys cover the starter shorting out internally?

(Only read about half the stuff typed)

Between starters and alternators, trim motors (drive and tabs) and radios with the power wire on all the time for the clock/memory and the bilge pump everything else should be switch hot only, so if the switch is off, one of these should be the culprit.


And glad to hear you got the cables/ battery cleaned up and connections tight, high resistant faults sure make things heat up and melt fast.

 

[LippCJ7]

Re: What is Draining My Battery?

not yet Rob but feel free to jump in most I have covered is pretty basic stuff but you know how it is until the basics are covered nothing is reliable, after checking out his other thread I am pretty sure this is a corrosion situation either in the wires or one of the components but I wanted to give him some knowledge so he can figure this out on his own, changing the battery out every time his boat will not start is not the answer and at some point the store is going to figure out that the battery is not the issue and then he is going to be stuck.

So my ideology is to teach him how to verify that every connection and wire is good or bad, once the system is checked out then he can check every component, the starter/solenoid is certainly suspect, but through all of this he should be able to identify a short himself, then we get Beer!!

 

[rbh]

Re: What is Draining My Battery?

Hey lipp hows it going this morning?

Anywho, if he's getting a big spark, and I mean big! every time he hooks up the positive or negative cable he has got a dead short somewhere.
Those items I mentioned that are constantly hooked up, pull the main feed/positive cable off and do a resistant test between the stud/hook up point and ground/block, the resistance/OHMs should be infinet, if it shows resistance theres your short.

 

[jcornell26]

Re: What is Draining My Battery?

Back with results, pics and videos!

I hooked up the BRAND new battery right before I did the testing. Did the Oms test like you said. The positive post was good at 0hms. The negative post on the other hand was jumping all over the place from 9.5-18.9. That is telling me there is a good amount of resistance somewhere then right?

After I did the testing I went to start her up and nadda. Below is the vid.
http://www.youtube.com/watch?v=JkN9zAbooX0&feature=youtu.be

I also attached a couple pics. One being the top of my battery and the other the starter. Their is already corrosion back on that positive wire and bolt that I cleaned off about a month ago. I know that's not good.

Again, I can't thank everyone enough for their patience and cooperation on this. Especially you Lipp, on helping a n00b out with the electrical aspect of things. Very cool of you.

 

[LippCJ7]

Re: What is Draining My Battery?

no doubt about the spark, problem I have is a big spark to him is relative to someone like us who spark all kinds of things LOL!!

as for the Ohms I'm still teaching him about a DVM's!!

As for how things are going, ok, me and wife are at odds right now, its going to be 100 degrees and she decided to load the truck camper and atv's and head to the mountains, I want to go to the lake, problem is I have one truck right now so I guess I get to ride the Harley, I bet she will be home tomorrow with the "Ok lets go to the lake" look!! I don't want to be on an ATV today its too freaking HOT!!

 

[jcornell26]

Re: What is Draining My Battery?

IRT the spark. When I tough the pos to the post, not every time but it will give off a tiny tiny little "poof" with a little spark. and I mean little. You can barely see it.