Battery draining...why? UPDATE

[bruceb58]

Re: Battery draining...why?

Re: Battery draining...why?

If you are measuring 12.5V, just put the multimeter in-line. A 10A draw would be lowering that voltage in no time at all. You can do any test on either the positive or negative side. If you want to use a clamp meter, and I still don't think you need to, you can do it on the negative battery cable side if its easier for you as well.

Do you get much of a spark when you remove a battery cable? If you are getting a 10A load with everything off, you would see a huge spark.

I am also wondering why your boat is wired to have an accessory position required at all. Most switches don't have an accessory position as it really isn't required. My FF is wired so that you can turn it on in any position. I am also winderring what else gets turned on in this accessory position. Are you sure its the acessory position and tou aren't really in the ignition position? When you turn off your boat, can you turn straight to this postion without going all the way to off?

Do you have a Harbor Freight near you?

Unfortunately, the cheap clamp meters don't read DC amps as far as I know...only AC amps. The cheapest AC/DC clamp meters are going to start out at $100. If it were me, I would risk blowing a $2 fuse or even a whole $8 meter before I spent $100 on something I may only use once.

 

[JustJason]

Re: Battery draining...why?

Re: Battery draining...why?

I would risk blowing a $2 fuse or even a whole $8 meter before I spent $100 on something I may only use once.

Good point, if you don't forsee using a meter beyond this job just order extra fuses along with a meter just in case. I don't know about 8 dollar meters, but sears has some cheapies over there.

 

[bruceb58]

Re: Battery draining...why?

Re: Battery draining...why?

I don't know about 8 dollar meters, but sears has some cheapies over there.

8 bucks...Harbor Freight!
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92020

 

[turbinedoctor]

Re: Battery draining...why?

Re: Battery draining...why?

As I was reading this I did not see or maybe I missed it, but what is the ratings of the battery? Cranking amps, reserve capacity or amp hours?

 

[KeyWestBoater]

Re: Battery draining...why?

Re: Battery draining...why?

I am also wondering why your boat is wired to have an accessory position required at all. Most switches don't have an accessory position as it really isn't required. My FF is wired so that you can turn it on in any position. I am also winderring what else gets turned on in this accessory position. Are you sure its the acessory position and tou aren't really in the ignition position? When you turn off your boat, can you turn straight to this postion without going all the way to off?

Bruce,

Sorry for not being clear about the accessory switch. The accessory switch is a separate toggle switch and not part of the ignition switch. When I run the FF I must have the access switch on but the ignition is off. Of course that's when I'm fishing and the engine is off.

KWB

 

[KeyWestBoater]

Re: Battery draining...why?

Re: Battery draining...why?

As I was reading this I did not see or maybe I missed it, but what is the ratings of the battery? Cranking amps, reserve capacity or amp hours?

TurDoc,

When I get home I will reply with the specs on the battery.

Thanks,
KWB

 

[KeyWestBoater]

Re: Battery draining...why?

Re: Battery draining...why?

The easiest way to test a charging system for a diode fault (which will cause a current draw back to the engine) is to put any old DMM on Millivolts AC and put the red to + and the black lead to - on the battery. With the engine running, if you get any more than .250 AC, then you have a charging system problem, and a current draw problem with the engine off.

Jason,
When I get home I will get the boat out of the garage so I can start it and try your test with my DMM.

Also, I don't think my DMM has an ampmeter in it. I got it from Sears a while back on sale for $15.

Thanks,
KWB

 

[KeyWestBoater]

Re: Battery draining...why?

Re: Battery draining...why?

Much to my pleasant suprise I discovered that my DMM has a ADC setting up to 10A. To try to keep from frying it I will test with one item turned on at a time. My question is since there is no clamp and only probes I suppose I will have to find the wire that feeds the FF and aerator and put the DMM in the circuit. Also to test the rectifier diode I guess the DMM leads go between the main pos battery cable and the battery pos post. Is this correct? Does it matter which way the pos and neg leads on the DMM are in the circuit?

Thanks again!
KWB

 

[KeyWestBoater]

Re: Battery draining...why?

Re: Battery draining...why?

Much to my pleasant suprise I discovered that my DMM has a ADC setting up to 10A. To try to keep from frying it I will test with one item turned on at a time. My question is since there is no clamp and only probes I suppose I will have to find the wire that feeds the FF and aerator and put the DMM in the circuit. Also to test the rectifier diode I guess the DMM leads go between the main pos battery cable and the battery pos post. Is this correct? Does it matter which way the pos and neg leads on the DMM are in the circuit? KWB

Hi. Does anyone have any info for me on this? I would like to test this today. Thanks for all your help!

KWB

 

[Don S]

Re: Battery draining...why?

Re: Battery draining...why?

I don't see this mentioned anywhere above, but why don't you take your fully charged battery to your local marine dealer or auto parts store and have it load tested.
From the sounds of things, I would be suspecting a bad battery.

When you are running on plane, you need to check your battery voltage with a DMM, (not the helm instrument), to see what your motors charging system is doing, you should be seeing around 14.5 volts, not 13.

 

[KeyWestBoater]

Re: Battery draining...why?

Re: Battery draining...why?

I don't see this mentioned anywhere above, but why don't you take your fully charged battery to your local marine dealer or auto parts store and have it load tested.
From the sounds of things, I would be suspecting a bad battery.

When you are running on plane, you need to check your battery voltage with a DMM, (not the helm instrument), to see what your motors charging system is doing, you should be seeing around 14.5 volts, not 13.

Don,
I have had the battery checked 3 times; 2 times by the boat dealer and once by West Marine, about 2 weeks ago. They both said the battery is ok. I mentioned this earlier. Also last year the dealer checked the charging system and said it was ok. I would guess that their test includes a load test? I haven't tested the charging system on the water, only on muffs at a fast idle it's putting out 13v. I wish and hope it's as simple as a bad battery. I blew both of my fuses on my DMM so I have to wait until tomorrow to do any more tests.

Thanks,
KWB

 

[bruceb58]

Re: Battery draining...why?

Re: Battery draining...why?

I blew both of my fuses on my DMM so I have to wait until tomorrow to do any more tests.

What were you doing when you blew them?

 

[JustJason]

Re: Battery draining...why?

Re: Battery draining...why?

I blew both of my fuses on my DMM so I have to wait until tomorrow to do any more tests.

I knew that was going to happen.

I haven't tested the charging system on the water, only on muffs at a fast idle it's putting out 13v

13V isn't high enough... as Don said, it needs to be about 14.5. Outboards with stator/permanent magnet driven charging systems need to have hi-rpms to fully charge. At low to mid rpms they are not charging or barely breaking even.

When I check these things I put my amp clamp on the postive cable (with the arrow pointing to the battery, remember, they are directional). I'll run the motor around 2500rpm and see what i'm reading on the meter, at that point, i'll have my battery load tester on the battery and i'll hit it, the amps reading should jump up. I do it this way because if you are using a good/full battery the charging system will only show 2 or 3 amp charge rate, when you load the battery while testing the charging system should jump up considerablely towards it's max rating.

 

[bruceb58]

Re: Battery draining...why?

Re: Battery draining...why?

I knew that was going to happen.

If you read his other post he put the leads between the positive and negative creating a dead short through his meter.

 

[JustJason]

Re: Battery draining...why?

Re: Battery draining...why?

If you read his other post he put the leads between the positive and negative creating a dead short through his meter.

I couldn't even tell ya how many people i've seen trying to measure voltage only to have the meter on amperage. Oh well.... at least it wasn't 24V, or even better, a trip battery bank at 36.... then the sparks really start to fly

 

[KeyWestBoater]

Re: Battery draining...why? UPDATE

Well here's where I am now with this. I took the battery to the local auto parts store. They said the battery tested good but showed that it wasn't fully charged. So I took it home and put it on the trickle charger for a few days. Then I brought it back and it tested again. Here's the results from both tests and the battery info:
Exide Nautulus Dual Purpose NC24
MCA 650
CCA 500

1st test: voltage 12.4, CCA 388 Test OK but needs charge
2nd test: voltage 12.9, CCA 373 FAILED!

I have been dealing with this problem for over a year and I was frustrated that now the battery is out of warranty and I've got to shell out about $100 for a new battery, so I called the dealer. They have it documented that I started bringing in the boat and battery for this problem whne it was about 8 months old but they said everything was ok. Without hesitation the parts manager said to bring the battery and she would swap it out. So I have the battery in my car and I'm bringing it there for the exchange after work today. I hope this is the end of my battery problem! I still would like to check the amps draw from the FF and the aerator but I haven't been able to find replacement fuses for my Sears DMM. When I find fuses I will let you know about that. In the meantime, thanks for everyone's help!

Thanks,
KWB

 

[mAlton]

Re: Battery draining...why? UPDATE

I still think I would strongly suggest a second battery. Why get stranded with a motor that can't start? Simple solution to a problem you never need to have. Good luck to you.

 

[Juniinc]

Re: Battery draining...why? UPDATE

I'm sure of that plenty of good suggestions above,,,I'm just too lazy to read.
How many onboard fuse U got?
1. start with fully charged battery
2. turn everything off
3. turn on batt SW
4. use a good muti-meter in AMPERE
5. see the current draw
If there is any
6. start pulling fuses 1 by 1 until it drops