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Old 07-21-2024, 06:50 PM   #1
forestb
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Battery, alternator or something else

I was driving today in my 62 c10 with a small block 350 and a 700r4 and it’s about 92 degrees outside. I start hearing a clicking sound from my ac which is running at full blast. I also noticed that my radio was cutting out when the ac was ticking. I thought o crud is something wrong with my ac motor. I turned off the ac and went to roll down my power windows and noticed that the radio goes out when the windows are running. I stopped at an auto parts store to buy a sun shade for another car and when I tried to start the truck it just made a ticking noise. I didn’t look at my volt gauge at that point. I removed my battery and had it charged for 30 minutes and then checked and it was bad. 6 year old battery. So I bought a new one. The truck stars right up like normal. I start heading home with ac running and radio playing and when I am around a mile down the road I look at my volt gage and it’s reading around 11 volts which seems low. So I turn off the ac and it stays in the same spot. I get home and let it idle and it doesn’t move it just stays at 11. I am used to it being around 11 or 12 volts. Did I get a bad battery? Is my alternator bad and I killed the first battery? I have plenty of ground strap going from engine to frame to cad. Maybe my engine to battery ground is loose. My wire to the alternator is tight and my belts are tight. I have hydro boost brakes and when I first started the truck I could hear a belt squeal when I pushed on the brakes but that went away quickly. The belts are tight.
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Old 07-21-2024, 07:05 PM   #2
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Re: Battery, alternator or something else

One more thing I noticed when trying to start it again when I got home was that when I was trying start it up it made a single click noise (like the one that happened when it would not start) once then started right up.
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Old 07-21-2024, 10:28 PM   #3
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Re: Battery, alternator or something else

Your new battery is likely fine. It takes 13V or so to charge your battery.
The clicking without turning over is typical of an undercharged battery.

Something is wrong. If you can't test it get someone who can. Throwing parts at electrical issues seldom works out.
Diagnosing is difficult but not impossible over the internet.
Need to know the type of alternator, if the regulator is still installed or is it one wire setup. The list goes on and you will need a volt meter.
You mentioned a Volt gauge, so I suspect the system isn't stock.
Cheers
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Old 07-21-2024, 10:44 PM   #4
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Re: Battery, alternator or something else

Electric is not my favorite subject, but I always heard that if your gauge reads negative voltage, it's a bad alternator because it is not charging the battery but if it shows excessive positive voltage, it's the battery because the alterneter is supplying all the power not the battery. It sounds correct to me but let's see what a better electrician has to say. I'm sure someone with more knowledge will chime in.
I don't know how I posted twice.
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Old 07-21-2024, 10:45 PM   #5
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Re: Battery, alternator or something else

Electric is not my favorite subject, but I always heard that if your gauge reads negative voltage, it's a bad alternator because it is not charging the battery but if it shows excessive positive voltage, it's the battery because the alterneter is supplying all the power not the battery. It sounds correct to me but let's see what a better electrician has to say. I'm sure someone with more knowledge will chime in.
I hate electrical issues.
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Old 07-21-2024, 11:25 PM   #6
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Re: Battery, alternator or something else

It sounds like you guys are feeling like it might be an alternator problem. I will remove it and get it tested. I hate trying to diagnose electrical over the computer also. It’s a power master one wire internally regulated alternator. Hopefully the local parts store can diagnose it. I will check back in with you guys if the alternator gets a clean bill of health.
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Old 07-22-2024, 04:54 PM   #7
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Re: Battery, alternator or something else

I hate electrical gremlins. Easy to first check with a volt meter at the battery while running. Should be around 14 volts I think if the alternator is working properly. Then check the wiring to the alternator and check directly at the alternator. I figured out that mine was bad that way.

Good luck!
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Old 07-22-2024, 09:40 PM   #8
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Re: Battery, alternator or something else

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Originally Posted by grubsster View Post
I hate electrical gremlins. Easy to first check with a volt meter at the battery while running. Should be around 14 volts I think if the alternator is working properly. Then check the wiring to the alternator and check directly at the alternator. I figured out that mine was bad that way.

Good luck!
So at the battery I am getting 12.01 volts and the same at the post of the one wire alternator. My gauge is still reading around 11 volts. It might be off by a volt.
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Old 07-23-2024, 03:24 AM   #9
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Re: Battery, alternator or something else

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So at the battery I am getting 12.01 volts and the same at the post of the one wire alternator. My gauge is still reading around 11 volts. It might be off by a volt.
You didn't say whether the engine is running or not. 12 volts at the battery when the engine is running usually means the alternator is not charging. When checking a battery without the engine running, a fully charged battery will read 12.50 volts. Depending on the load being applied at the time of the test (electrical items turned on), a functioning alternator will produce 13.7 - 14.2 volts at the battery. The big wire on the back of the alternator is simply the other end of the positive battery cable, so the 2 points will always read very nearly the same voltage (+/- .1 - .2 volts), engine running or not. The 11 volt reading at the in dash voltmeter is probably correct and just represents a 1 volt drop over the length of the wire.

Based on what's happening now, I doubt the first battery was bad - just improperly tested.. A 30 minute "quick charge" will not build enough charge in a dead battery to give an accurate test.. 90% of the time, the battery will always test "bad".. A dead battery needs a slow charge for a few hours to bring it to full charge.. Never use the alternator to charge up a dead battery. Alternators aren't built to work like that.
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Old 07-23-2024, 10:54 AM   #10
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Re: Battery, alternator or something else

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You didn't say whether the engine is running or not. 12 volts at the battery when the engine is running usually means the alternator is not charging. When checking a battery without the engine running, a fully charged battery will read 12.50 volts. Depending on the load being applied at the time of the test (electrical items turned on), a functioning alternator will produce 13.7 - 14.2 volts at the battery. The big wire on the back of the alternator is simply the other end of the positive battery cable, so the 2 points will always read very nearly the same voltage (+/- .1 - .2 volts), engine running or not. The 11 volt reading at the in dash voltmeter is probably correct and just represents a 1 volt drop over the length of the wire.

Based on what's happening now, I doubt the first battery was bad - just improperly tested.. A 30 minute "quick charge" will not build enough charge in a dead battery to give an accurate test.. 90% of the time, the battery will always test "bad".. A dead battery needs a slow charge for a few hours to bring it to full charge.. Never use the alternator to charge up a dead battery. Alternators aren't built to work like that.
The truck was running yesterday when I just tested it and it read 12.01 volts.
Don't worry I didn't try and use the alternators to charge a dead battery.
It was the auto parts store that tried to charge the battery and then tested it on Sunday.

So at 12.01 volts we are definitely thinking that it is a bad alternators?
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Old 07-23-2024, 02:11 PM   #11
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Re: Battery, alternator or something else

bad alt if the fan belt is tight
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Old 07-23-2024, 04:32 PM   #12
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Re: Battery, alternator or something else

I was just talking to a coworker and he said that a good way to check your alternator is to start the vehicle and then unplug the battery. If the truck keeps running than your alternator is working. If it stops then you know that the alternator is not working.
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Old 07-23-2024, 06:14 PM   #13
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Re: Battery, alternator or something else

if you want to check the alt, lay a screwdriver behind the alt at the bearing if it is charging there will be a magnetic field that will pull the screwdriver to the bearing while it is running
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Old 07-23-2024, 08:41 PM   #14
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Re: Battery, alternator or something else

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The truck was running yesterday when I just tested it and it read 12.01 volts.
Don't worry I didn't try and use the alternators to charge a dead battery.
It was the auto parts store that tried to charge the battery and then tested it on Sunday.

So at 12.01 volts we are definitely thinking that it is a bad alternators?
Before you run out and buy an alternator, have yours checked (not Autozone or O'reillys) by a reputable facility.. If it checks ok, you have a wiring problem with the charging circuitry. Pointing directly to THAT problem is next to impossible over an internet forum.
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Old 07-23-2024, 08:46 PM   #15
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Re: Battery, alternator or something else

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I was just talking to a coworker and he said that a good way to check your alternator is to start the vehicle and then unplug the battery. If the truck keeps running than your alternator is working. If it stops then you know that the alternator is not working.
NEVER EVER DO THAT!!!!.. The alternator will not have a place to put the output, plus it will "see" a totally dead battery, go wide open, and it will almost instantly blow the alternator.. Is your "coworker" a trained automotive technician??? With that statement, I doubt not.
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Old 07-23-2024, 08:52 PM   #16
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Re: Battery, alternator or something else

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Originally Posted by RustyPile View Post
NEVER EVER DO THAT!!!!.. The alternator will not have a place to put the output, plus it will "see" a totally dead battery, go wide open, and it will almost instantly blow the alternator.. Is your "coworker" a trained automotive technician??? With that statement, I doubt not.
HaHaHa. He was in India. HaHaHa
It seemed sketchy when I heard it. Unplugging anything with the engine running sounds like a bad idea
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Old 07-23-2024, 08:56 PM   #17
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Re: Battery, alternator or something else

I will have it checked
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Old 08-07-2024, 10:06 PM   #18
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Re: Battery, alternator or something else

So I took your advice and found an alternator/starter rebuild shop to have the alternator checked. When I got there it was pretty much a garage door halfway propped open with no sign but I knew I was in the right place when I found the little old guy inside surrounded by used alternators and starters. He quickly checked it using an old diagnostic machine and told me it was no good. He started taking it apart before I got a chance to say anything and started diagnosing it. Then told me he could have it fixed the next day. I installed it after work and it now charging just below 14 volts. It took longer than one day to get it back because we both came down with a cold the next day.
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Old 08-08-2024, 02:54 AM   #19
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Re: Battery, alternator or something else

Glad you got it fixed. There is still one shop by me. Used to be a couple but, not anymore. Hope you get over your cold soon....
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Old 08-09-2024, 08:34 PM   #20
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Re: Battery, alternator or something else

You and the alternator guy both got a cold on the same day??
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Old 08-09-2024, 10:05 PM   #21
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Re: Battery, alternator or something else

I had no symptoms when I dropped off the alternator. The next day I started having symptoms. That was a Friday. He called me that day to pick it up but I told him I was too sick to come get it also I didn’t want to get him sick. On Tuesday when I was feeling better I stopped by his shop to pick it up and it was closed. The shop next door said that he had not been there on Monday and he was probably sick or out of town. I called him the next day and he said he was sick. I don’t know which day over the weekend he started getting sick. It took him a couple of days longer than me to feel better. So the quick answer is no. He got sick a couple of days after me. I think I unknowingly got him sick.
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Old 08-09-2024, 11:22 PM   #22
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Re: Battery, alternator or something else

I'm glad you got that fixed and you're on the mend, that sounds like a good shop to know about. What a story, I guess you shouldn't have spit shined that alternator before handing it to him!
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Old 08-10-2024, 09:42 AM   #23
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Re: Battery, alternator or something else

It’s funny you find a shop like that but how many alternator rebuilds are you really going to need over the years?
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Old 08-10-2024, 10:35 AM   #24
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Re: Battery, alternator or something else

Unfortunately, my alternators last 1 to 4 years driving about 5000 miles per year. I think the diodes and bearings nowadays are both made from melted down pot metal quadrajets and alternator casings with a little bit of dirt thrown in for good luck. :-)
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Old 08-10-2024, 12:24 PM   #25
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Re: Battery, alternator or something else

The power master alternator I have been using has lasted maybe 10 years or more. I’ve been very happy with it.
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