Battery issues- Mom's 92

[dpuckett]

My mom's 92 has been discharging the battery lately (or the alternaotr hasnt been charging it). It began that if you let it sit for 4-5 days without starting, it wouldnt heat the grids AND start, but it'd do one or the other. Now it wont hardly start overnight, regardless of block heater usage. She put a 40amp charge on it for 10min, then took it to O'Reilley's and had them hook up their machine to the battery and the battery checked out fine, as did the alternator. Now, we all know that hooking up leads to the battery isnt the best way to test an alternator, and that batteries can pass load tests and be "good", so I'm going to take those results with a grain or two of salt. I had AutoZone tell me in 99 that I had a good alternator, only to have it die the next night in central NE.



I did a search here, and concluded that the following possibilities-

1) Diode in alternator gone bad. Will this show up on a test stand when I take it to the local alternator/ start shop? If not, how do I go about checking it?



2) Something internal in battery- it'll pass a load test, but not hold a charge. It is a sealed type battery (I'm as fond of those as I am of greaseless u-joints ), so no way to check water level.



3) Higher than normal amperage draw of an accessory- radio, brake controller, etc. Though she has no aftermarket stuff hooked up, and I think all the lights go out at night.



4) Ground issue.



I told her to remove the battery and alternator and take them into the local shop (which has done well for me in the past) and have THEM check it out. I also told her to check and double check her grounds and make sure they were making good contact.



Is there anything else to check? Truck is 100mi away from me, so it's not like I can run over and hook stuff up to it.



Daniel

 

[JLEONARD]

Daniel,

I had a battery that passed a standard load test but didin't have enough juice to crank the Cummins. So forget the load test IMO.

If you do a voltage check across the batt terminals while it's running and you get 14. 2 (or whatever ours are supposed to have I don't have the manual handy), then the charging system should be ok.

Last year mine was only putting out 13. 8 or 13. 6 and that's when I put in a new alt and that got it back up to 14. 4 and it's been fine.

I just replaced the battery yesterday, as when the weather got into the single digits here last week she was cranking over slow... she was putting me on notice that is was time.

Once a battery gets to the point that it's weak, it starts to put strain on everything electrical so I never mess around and wait for the starter, realys, alt, etc to burn up only because I'm too stubborn to buy a battery... I've been there as have most of us.

Of course it could be bad battery connections, or a bad ground, but I assume those have been ruled out as they are easy to check.



Hope this helps.

Jay



EDIT... by the way I got 4 full years out of that battery... a single Optima Red Top (800 CCA)... and I consider that excellent service considering I run the truck almost every day winter and summer, it sits outside all the time, and I had that alt issue, and the lift pump failure that stole a good deal of cranking life

 

[boatpuller]

If you think the battery is loosing its charge all by itself at night, just have her disconnect the battery when she parks it for the evening and hook it back up in the morning when she needs to start the truck. If it won't start the truck in the morning then you know it's the battery if it was able to start the truck before being disconnected, if it does start the truck in the morning you will know that something in the truck is draining the battery.

 

[DPellegrin]

The charging system voltage should between 13-9 and 14. 2. If you suspect that there is a small current draw when the vehicle is parked and everything is turned off, you can check this by taking a test light and connecting it in series (one path to ground) between the negative cable and the negative battery post (just be careful about making sparks around the top of the battery). The light will not light up if there is not a current draw, if it does then you have a problem. There are also some good quality volt-ohm-meters (VOM) like a Fluke or Simpson, that have a built in current stunt you could connect the same way as the test light and it would tell you the actual current draw in amps that is leaving the battery. But I would do the test light, test first. If there is a current draw you are going to have to start unplugging fuses, relays etc. to find the source of the current draw.



One last thought, most of the time the battery is the source of charging and starting system problems, so make sure your confidence is high that the battery is good.



Good Luck

 

[PToombs]

Daniel, I had a bright idea, but these trucks don't have an amps gauge to check diodes!

Check charge voltage with accessories off, then on. Voltage should stay close to the same. I would check for a drain also like DPellegrin said. I have seen allegedly good alternators with a short.

Good luck!

 

[MMeier]

I'd say it needs a new battery, had to put one in my '93 about a month ago.

 

[dpuckett]

What is the general life expectancy of a battery? I was thinking 4 years, which would be putting this one a little short (I think it's 3), but it IS in a high humidity area, and humidity shortens the life of lots of things. Jay's satisfaction with his 4 year Optima made me ask.



Might try swapping batteries with her next weekend, as I plan to go cut a load (or 2) of firewood. Got the wood furnace wired, just gotta hook the rest of it up.



Daniel

 

[GIT-R-DONE]

Life expectancy of a battery is up for debate. The one in mine (interstate) is marked/punched out, is over 5 years old and still working fine. Try like you said and swap batteries and see what happens, if she isnt in dire need of it and doesnt do alot of traveling. Dont want her getting stranded somewhere. :-laf

 

[dpuckett]

UPDATE:



She unplugged the battery cable, then hooked it back up and noticed the radio now worked. So, she has taken to turning the radio off when she gets out. Theory is, something in the radio was pulling enough amps to drain the battery.



WIll let y'all know if it works.



DP

 

[tugboatphil]

Daniel, we used to have a car that had a CD changer in the trunk. I had the battery run down just like you described, and it was well before it should have worn out. After charging it and running for several days, with no problems, I was walking past it. I heard a noise in the trunk so opened it to investigate. There were no CDs in the changer, but it was trying to find the next one. I couldn't stop it from the radio, so I just pulled the plug on it.

We totaled it that winter and I never did figure out the problem.

 

[JLEONARD]

Tugger, I'm impressed... . a fix without tape!!:-laf:-laf

 

[dpuckett]

Yeah, but it did involve just pulling the plug. He should have taped the ends, though.



DP

 

[tugboatphil]

I forgot to mention... . I used half a roll to cover the plug and receptacle.

 

[PToombs]

Duct tape is like the Force. It has a light side, and a dark side.

And it holds the universe together.



:-laf :-laf

 

[JLEONARD]

Oh could I tell a couple of duct tape stories... as I'm sure most others can. LOL