Battery won't stay charged

[Youngbone]

Ok, so I'm swapping my toyota for an 85 with a solid axle and a 3.8 buick v6 engine in it. You charge the battery and it starts like up to 5 times, and then the battery goes dead. The guy had the battery and alternator tested, and both tested good. So what's the next step to figuring out why the battery won't stay charged? I don't want to waste money and buy a new battery if the alternator is really just bad and will mess up that battery. What do you guys suggest I do? Thanks,

CJ

 

[bobbed_84_toy]

Sounds like a flat battery. Try another battery in it and see if it goes away

 

[lilyota]

Who tested it smucks they told me i had bad alternator good thing I kept it, it still working to this day it was a bad battery

 

[Youngbone]

Yeah it was schmucks, but they said both the alternator and the battery was good. So should I just start with a battery first? Also, I still haven't figured out my damn tail lights .

 

[JOOP]

Did they put thhe alt on a tester? Not the thing that they roll out to your car. If you pull the alt they or any auto store can test it and give you a true answer. The tester that rolls out to the car isn't 100% IMO.

 

[Youngbone]

Yeah they took a little hand held device to test the alternator so I don't know if it's 100 percent sure. I just don't know if I should get a new alternator and battery or just start with the battery first or something . Like I said the main thing is I need to fix these tail lights to make it driveable at night time, and I don't even know how to tackle that one yet. Thanks for all of your help guys, and if anyone else can help me let me know.

CJ

 

[skrause]

Did they put thhe alt on a tester? Not the thing that they roll out to your car. If you pull the alt they or any auto store can test it and give you a true answer. The tester that rolls out to the car isn't 100% IMO.

And you're assuming they know how to use their bench tester?!?!?! :haha: :haha: :haha: :haha: :haha: :corn:

 

[cheesemaker]

Here's what you do! First look at the battery's sides, the ends, are they swelled out like a woman with wide hips? If they are, then the battery is bad or the alternator is over charging!
Put a charger on the battery over night. Make sure it gets a good charge! Then in the morning put the volt/ohm meter on the battery, what is the voltage? A good charge should be 13+ volts! If it's less than that the battery is bad! Next, start the vehicle, and with the volt/ohm meter still on the posts, see what the voltage drop is under a starting load! It shouldn't drop below 12 volts (not 100% sure any chilton/haynes might have this), if it drops significantly then the battery is bad!
Finally, with the vehicle running, see what the voltage is in the battery while the alt. is charging it! Should be 13.5 to 14 volts. Then turn on all the lights, heaters and anything else in the vehicle, and see what the voltage is at now! If the voltage is lower than 13 volts then the alt is bad! Generally the diodes in the alternator goes bad!

Now this is just a basic list of things I check for before I go and find a professional mechanic! I don't do the les schwab, schmuck's, or napa testers, I've had way too many of them tell me my batt/alt are good when they read false signals. If the battery is good, but not fully charged it will give the tester false readings!

One other thing to check for, is to look for a little sticker on the battery. It will have a letter and a number! The letter will represent the month of production, ie, A~jan, B~feb, and so on! The number will represent the last digit of the year of production, ie, 0~2000, 1~2001, and so on!

Hopefully this helps! I would lean towards a bad battery! If it only lasts five cranks, then I would assume that it isn't holding a charge! Which means the battery has been well used. Remember that heat is a batteries worst enemy! Heat from a motor, over charging, or drawing more from the battery than the alternator is replacing! All these will heat up a battery! And when the battery heats up, the lead plates will warp and start touching other plates causing shorts in the battery thus reducing the amount of voltage that the batt. will put out!

 

[84Toyota4x4]

One more piece to add to the above post, after charging it all night, I like to hit the lights without starting it for about 30 seconds to kill the surface charge if youre going to test it RIGHT after you pull it off the charger. If you disconnect it and then let it sit for a while before you test it, disregard.

~T.J.

 

[JOOP]

And you're assuming they know how to use their bench tester?!?!?! :haha: :haha: :haha: :haha: :haha: :corn:

Well I know I do, and the bench tester is pretty much idiot proof. Ours displays the alt. on the screen, tells you what adapter to use and where to hook the wires up. Pretty simple actually. But I work at AZ, not schmucks :flipoff:

 

[skrause]

Well I know I do, and the bench tester is pretty much idiot proof. Ours displays the alt. on the screen, tells you what adapter to use and where to hook the wires up. Pretty simple actually. But I work at AZ, not schmucks :flipoff:

Last time I took one in it was the older machine with one meter, one needle, two scales (V/A), and a switch. Forking maroon didn't know he had to flip the switch to do the load test and tried his damnest to convince me a single analog needle can display voltage and amperage at the same time. He claimed alternator was good, what was left of the brushes wholeheartedly disagreed with him.


Mabye you know what you're doing, but I doubt 9/10 or more of the guys working there know their current equipment any better. :flipoff:

 

[Qman]

Before you replace anything charge the battery. Then disconnect the negative cable. Let it sit overnight. Reconnect the cable and see how the battery fared over night. If it starts the truck and holds a charge overnight it's OK. Look for a dead short somewhere. I have a similar problem with my '84. I just disconnect the battery until I find the draw.

Good luck.

 

[Long&Low]

I bet it's the battery, it won't hold a charge, you got a dead cell.

 

[toyparts]

start the truck ,,,disconnect the neg side of the battery WHILE THE TRUCK IS RUNNING If the truck keeps running your alternator is good ! BUT YOUR battery IS NO GOOD
IF THE TRUCK DIES WHEN YOU DISCONNECT THE BATTERY THEN YOUR ALTERNATOR IS DEAD
and your battery is most like;y dead too !
takes about a minute and a half to figure it out

 

[BustedPinion]

Yeah it was schmucks, but they said both the alternator and the battery was good. So should I just start with a battery first? Also, I still haven't figured out my damn tail lights .

that tester they use is junk, it will not pickup on a a broken plate in a battery, nor will it pickup on a issue load testing until it happens, IF THEN. you have to have them run a start test a few times in a row til it fails under load. if you have a 650 CCA battery and get 5 starts, then its failing under load. i just got a undesized battery in my truck, sbc350 and a 650 CCA and cranked on it for like an hour this morning and it never went down, and thats a walmart (N)everstart POS battery ..

buy a battery and test the alt.

 

[Youngbone]

I think I figured out what was running constant power. The old toyota ignition is still in there and has to be turned to the on position in order for the truck to start, but if I shut that off then I can't start the truck with the buick ignition. So I think turning both ignitions off is working, not sure yet will have to check in the morning.