battery post mystery

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Raider L

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I have had a peculiar problem with my battery for many years now and have no idea what in the world could cause such a thing. I need help figuring it out because it has got me puzzled to no end.

At random times, it could be a month, it could be three or four months or twice a year just any time, I'll get in the truck to start it and it wil click one time and then nothing at all. I have a lot of gauges as any of you know me, when this little electrical thing happens I've learned that when I get that one click the next thing I do is look at my gauges. When the key is to the "start" position the needles will be flicking back and forth but no starter action. I've learned that it's a sign the positive battery cable end needs cleaning. Now, let me say this I'll put my battery parts up against anyone's for cleanliness. Looking at them there is not one single speck of anything on the cable end or the post, cables I mean spotless but it's not making connection somehow.

So, I'll get the battery brush out and my half inch wrench, take the terminal off, using that stiff a** brush in the battery cleaner and brush the hell out of the inside of the terminal. Then I'll put the post brush end on the post and twist it on there good. The put the cable end back on the post, tighten it up snug, get in the truck and it cranks up like nothing happened.
Now, understand there is never the slightest sign that the terminal needs cleaning. It's already clean as a whistle, perfect in every way, cable ends to where the wire goes into the terminal, clean. And it's clean when I have to take it off and do the little drill with the battery brush. Not the slightest sign of corrosion or anything.
So a long time ago I bought a large spray can of that battery terminal spray that's red in color, you know, that stuff? Well, that little "click" problem happens even with the spray on it, just a little longer in between times but it still does it as soon as the spray goes away.

Anybody ever heard of anything like that? Clean post, clean terminal end, absolutely nothing on either one, I mean clean now! But some how at random times without the smallest clue something is about to happen "click" and it won't start. I get the click and then I know what it is and I have to clean the post whether it needs it or not, which is never but afterwards the truck cranks like nothing ever happened. So it must have needed something, what, I don't know but doing the brush seems to solve the problem, whatever that is because it's not that the thing was dirty. And I have lights and everything after the "click" to because it's happened at night as well. But anytime the click happens, and the gauge needles are flicking back and forth I know it's that positive cable end. I clean it and everything is back to normal.

Ever heard of anything like that? Anyone? And it's been going on for years and years even if I have a new battery or not to. That's the mystery. It even happens with a new battery. It's never the starter, never the cables, never the end going into the terminal even though I've at times took the cable out of the terminal and cleaned the battery cable wires that go into the terminal. It doesn't matter. A couple, or a few, or a couple of weeks, or whenever it wants to..."click". It happened to me tonight. I went and bought a new battery and put it in. So, we'll see how long it takes it to do it, and I'll post again to prove it. I'll take a picture of it so you can see how clean it is before I take the terminal off and after, so you can see how clean the terminal is and the post and you tell me if you think it needs cleaning!!
 
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mtnmankev

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Two of my vehicles, my 84 K10 and suzuki samurai did the same thing.
Totally unpredictable when the posts would be so cruddy they lose connection.
They would start and run fine no issues, then out of the blue, I am late because I need to clean the terminals.
It's a good chance the space aliens are messing with the earthlings again.
 

AyWoSch Motors

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Never had that happen to me, but I have 2 guesses.
1: the battery stud or hoop connector that connects at the starter end is frayed/broken/dirty/corroded.
2: the actuall cable is full of corrosion inside the rubber jacket, and the wires aren't connecting
I've seen cables that are like twice as thick as they should be, because they're full of corrosion, and it pushes apart the wires.

It's possible that the action of you taking the cables off, and cleaning them, jostles them around enough, that the poor connection they were getting elsewhere is reconnected for a while, or enough crust comes out of the end of the wires to work.
 

Corvette Ed

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Never had that happen to me, but I have 2 guesses.
1: the battery stud or hoop connector that connects at the starter end is frayed/broken/dirty/corroded.
2: the actuall cable is full of corrosion inside the rubber jacket, and the wires aren't connecting
I've seen cables that are like twice as thick as they should be, because they're full of corrosion, and it pushes apart the wires.

It's possible that the action of you taking the cables off, and cleaning them, jostles them around enough, that the poor connection they were getting elsewhere is reconnected for a while, or enough crust comes out of the end of the wires to work.
X2 especially #1
 

Turbo4whl

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The first thing to check, is the battery lead loose at the starter stud? Like Ayden stated, moving cable can be regaining the connection.

You can load test the cable for corrosion that you can't see inside. With your volt meter leads on each end of the cable, battery positive post and the starter stud. The voltage will be zero, or close to it. When the engine is cranked, the cable will add resistance. You will be able to see this on the volt meter as the engine starter is cranking. Up to one volt is common and not an issue. If you see 2, 3 or even 4 volts showing on the meter when cranking, the cable has an issue.

This is called a voltage drop test. You can check the ground lead the same way. One lead of the volt meter on the negative battery post. The other lead at the bolt where the ground lead is connected.
 

SirRobyn0

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@Raider L I'm going to assume that even though square bodies came factory with side terminal batteries you have converted to top post? My assumption comes from you saying you need a 1/2 wrench for the terminal and most side terminals are 5/16". Same thing I'm about to say applies to side terminals, but no washers obviously.

My thoughts, cable corroded inside the insulator. Like Ayden said. Then when you remove that terminal to clean it you move the cable enough for it to work again for a while. That's a real possibility, but in your case I think it's the terminal. I think the problem is you are using the wrong products on your battery. The trouble with that red spray is you put it on top of the terminal, and the acid that causes the corrosion comes from the bottom. We have had so much trouble with that red spray sealing in problems that we won't use it at the shop. Here's what you want to do. Buy battery terminal washers, like these, acid can't get past the washers. Also buy some dielectric grease. Clean those terminals to a shine then install the battery terminals, a thin layer of dielectric grease on the posts and reassemble. If the problem is the actual terminal and not inside the cable this method will provide long lasting solution.

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Wumbo

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The US military had a problem with some missile guidance systems corroding and causing failures. They cleaned the troublesome connectors with Deoxit, and the problem went away.

Allegedly.
 

Raider L

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Super thanks guys!! I never thought about corrosion inside the cable, and I'll bet you that is exactly what it could be. As far as those washers, I used to use them and don't recall having this problem when I used them. It started after I stopped using them.

@Turbo4whl I will do this! I'll bet you it's worse than 2, 3, or four volts because these cables have been on the truck since it was rebuilt. I have been reading ya'll's posts about larger battery cables carrying more, and better juice to the starter, etc..for some time now. I think I'll use welding cable of suitable size. I've just got to figure out how to rebuild the wires and positive cable going to the starter since I built those wires and wrapped them in heat jacket like used on aircraft.

I claim gremlin's are doing this!
 

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Rip apart that side post rubber ****, youll expose something like this with clearly visible corrosion, contact, wires, etc. If it is good, you only need to grind down the little indents you see in the circle, 4 of them, because its stamped so that it "locks" into the lead I think or perhaps one of the spacer washer things. Either way, you just file or grind the side that isnt flush/flat, and then its flat. you now have a brass /copper depending on year / source of cable(this one may be from a later truck, but maybe square) LUG that you can do much more logical things with that
1) are just better than what GM did
2) are visible and you can monitor any corrosion buildup or issues over time because you arent masking the issue
3) you just have more options. the quick and dirty of how to fix this once like this is to buy 2 brass marine type terminals (with a stud and a nut, usually a wingnut), with a proper washer and also with the ability to add on power or ground wires to a stud if needed you have a functional post that will work just as good if not better than the OE(No lead on the post/cable, only on battery if it is a normal lead acid battery), and with a proper battery cable spray stuff you will be fine for a long time.


This is of course assuming your factory power cable is fine. if i recall correctly, there is...only one power lead on a square? I know a lot of gm cars had one straight to starter and then one to a fuse box usually but I dont actually know what a stock square had for cabling.
 

Raider L

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@AuroraGirl,
Sorry this is so long.
Yes, you are correct about those side post cables. But when I bought this truck the battery had been changed by the previous owner, he had changed the battery to a top post battery. When I got the truck I assumed the battery was the correct one for the truck since the only side post batteries I had seen were in trucks later than '74, and in cars. I thought it was strange then, who ever heard of a "side post". I thought it was stupid, and I could see right then problems with getting the cable tight enough. It's not like you are tightening down a bolt and nut. All you had was this "screw" there on the side of the cable, and as big as the cable lug was with all that big plastic and then this short little screw thing, and that was it. If you one time got it a little cross threaded you were screwed, no pun intended,

So apparently the PO was thinking like me and changed it out. Funny, it wasn't until I got my factory manual after owning the truck for many years that I just happened to be reading through it and discovered that my truck was supposed to have a side post battery in it. I was shocked! I thought those kinds of batteries came in much later cars and trucks than mine.

Last night I had to tell the guy at Advance Auto Parts that he had to ignore what the computer said about my year truck because it's going to show a "side post" battery. What I wanted him to do is use the class number of it to show me about what size the battery would be. Also, whether it had caps or was a sealed one. I like caps so I can check fluid levels and specific gravity in each cell. Because even a inch wider battery would make it to large to fit in the battery tray. So after he got the number I went over to the batteries and looking at the size one the computer showed, if I could find one with the top posts, caps, and the right way the posts were facing! In my truck the positive post needs to be on the right. Because as you know the posts are close to the side not in the middle, but the neg. and pos. posts can be on the opposite side from how your cables are. So I had to look at that as well.

Also, it couldn't be to high a amperage either. The latest ones are 800 and 850 amps. Holy smoke! I only have my engine, my head lights and turn signals, and instruments, and a factory am-fm radio. That's all. I don't need that much amperage. I have always got a 675 amp. battery and have never needed more than that. So the nearest I could get was a 700 amp, the 675's were a battery that didn't have as long a guarantee as the top of the line one I've always got. There were some 675's in the guarantee range but they were small, to small. I didn't get that, they were about the size of a golf cart battery. What the heck are those for?
 

AuroraGirl

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I mean, an electric golf cart battery is ******* HUGE and HEAVY and... 6 volts? I dont remember how they were but I know more than one was used so the voltage was either 6 or 8 maybe 10 or 14.. it was odd.. anyway I get what you mean. the size of the battery, overall, is gonna not matter too much for you other than reserve capacity most likely. The specific design construction etc would all be very relevant because I can buy two 78 group size batteries and they be very very different, maybe almost 15-20 pounds different, and still be the same outside pretty much. That would mean we are looking at a density of the inside for that, which my example of 15-20 pound was my AGM from northstar which is over 50 pounds on its own but I can find a 30 some pound 78 not too hard , but a lot will find themselves in the 40 some pound im sure

Anyway, that is a different construction and you definitely dont need that for your truck
Although for the best warrantys you usually need to be apart of a club store kinda thing or buy a premium battery. I would just stick to the simple for your truck since you keep it without bells and whistles and dont live where its -40 on a sunny day in january and 20mph winds etc Lol.

There is nothing wrong getting more CCA that is just how many amps at 32 f your battery can provide for starting which with a old school starter might not be a bad idea to keep the CCA higher than original rated/you had before. Not counting for sulfation and sitting behavior, but in a battery, if you ask of it a large % of its ability to deliver crank amps or just in general, those deep plunges on the battery esp when cold will wear them down, so as i said not counting that other stuff, a higher rated battery wont be stressed so hard doing the same amount of work. However your truck has a lot less electrical loads and so much reserve and capacity wont really do much esp if you never leave the lights on etc. your battery is kept charged at a simple low amp rate which is good for temperature and not boiling or evaporating off any electrolyte, it wont be so helpful in controlling sulfation because a little over-charging especially in the right way is good for a battery to keep the lead clean on the inside which a SI series alternator cannot do but CS and AD alternators can partially do to an extent. and assuming your voltage isnt cranked up too high either, you might actually like an AGM which if you had too high voltage your SI alternator would probably cook it if you drove long enough. but the amount of time that would take to be detrimental i have no idea

long story short, yeah those middle posts are weird. negative near the fender, positive closest to the engine, battery cable thats barely enough for that, all i need :)
however the 2 plowing seasons I really noticed the dive on the volt gauge the battery takes using the hydraulics with the starter motor running it. i would definitely eat batteries like mad if that was run a lot. even with a good alt.

If I recall, a square is a 34/78 or a 78 group size battery which would be pos post closer to firewall, closer to engine if you mount on the passenger side normal tray. the 78r would be the same concept but the negative would be on other side so not bueno for your use. 34 is the top..wait.. 78 is the side... one of those is the side post one, I think 78, and 34 is the top post , and the 34/78 is just a combination battery with both top posts and side posts in the right arrangement its what is in my square this minute. Well. sort of. i took it out and put in my car but then I needed to move square and my marine battery was chilling out so I put the marine battery in and put a piece of leather over the stud on postitive because fully closed the battery only needs to hop a tiny bit and its shorting out on the hood lol
 

Raider L

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@AuroraGirl,

Now, the next thing I need to do is replace those old battery cables. They've only been in there for way over twenty-five years because I just cleaned the old ones that have been in the truck for no telling how long, cut them to the new length and reattached them to the battery. They looked okay on the outside, and when I trimmed the ends off and soldered connections to the battery cables the copper wire was clean and bright. So, it looked okay to me but that was twenty-five years plus ago. I was telling @Turbo4whl last night that I'll replace those old battery cables with welding cable.
 

Raider L

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@AuroraGirl,

All batteries are to heavy for me now. My son was on his phone doing business and I wanted to get the job done right then because it was already eight o'clock and my pain meds had already wore off. So I parked his car, to go get the battery, close enough to my truck so it was a very short distance to the open engine compartment. I used my only good arm and got it in quick. Ha, ha. I don't put anything off. If I was in good enough shape I'd be outside at midnight working.

Yeah, I was reading about those CS alternators tonight. The new alt., another 10 SI, I bought a few months ago started acting up so I pulled it and put my rebuilt one back in the truck. It's the factory alt. that's been rebuilt about two dozen times (joke), but the last time I rebuilt it, after buying that first new alternator I ever bought for this truck I've had since '81, I went the whole nine yards and bought a new core, the armature? the thing with all the windings and the curved steel finger looking things, new housing bearings, new rectifier bridge, new diode trio, and the best voltage regulator I could find that's a 14.2 volt one. I cleaned the housing halves to look new and put it in the truck when the new, new one started acting like the voltage regulator was doing something weird. I didn't want that stupid thing to fail so I yanked it out.

But that wasn't the reason why my battery appeared dead last night. It was the dang cable again, like @Turbo4whl suggested. You know I never thought about the corrosion being down inside the cable insulation. I'll get a new cable and I'll cut that old one down the middle and see where the problem is.

The number on the new battery isn't any series that goes to the truck. I really don't have any idea what it goes to. It was a 24-2 or something like that? I picked it for size, amp. output, and post location. Those little batteries I said I was looking at last night just looked like some small vehicle battery. Do you think they might go to a small car? They must have been about 7" square and put out about 500 CCA. Know any car that would take a battery that little? Yeah, now that you mention it those golf cart batteries are huge, and like four of them, or more, all wired together. Yeah, they're long to.
 
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AuroraGirl

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@AuroraGirl,

All batteries are to heavy for me now. My son was on his phone doing business and I wanted to get the job done right then because it was already eight o'clock and my pain meds had already wore off. So I parked his car, to go get the battery, close enough to my truck so it was a very short distance to the open engine compartment. I used my only good arm and got it in quick. Ha, ha. I don't put anything off. If I was in good enough shape I'd be outside at midnight working.

Yeah, I was reading about those CS alternators tonight. The new alt., another 10 SI, I bought a few months ago started acting up so I pulled it and put my rebuilt one back in the truck. It's the factory alt. that's been rebuilt about two dozen times (joke), but the last time I rebuilt it, after buying that first new alternator I ever bought for this truck I've had since '81, I went the whole nine yards and bought a new core, the armature? the thing with all the windings and the curved steel finger looking things, new housing bearings, new rectifier bridge, new diode trio, and the best voltage regulator I could find that's a 14.2 volt one. I cleaned the housing halves to look new and put it in the truck when the new, new one started acting like the voltage regulator was doing something weird. I didn't want that stupid thing to fail so I yanked it out.

But that wasn't the reason why my battery appeared dead last night. It was the dang cable again, like @Turbo4whl suggested. You know I never thought about the corrosion being down inside the cable insulation. I'll get a new cable and I'll cut that old one down the middle and see where the problem is.

The number on the new battery isn't any series that goes to the truck. I really don't have any idea what it goes to. It was a 24-2 or something like that? I picked it for size, amp. output, and post location. Those little batteries I said I was looking at last night just looked like some small vehicle battery. Do you think they might go to a small car? They must have been about 7" square and put out about 500 CCA. Know any car that would take a battery that little? Yeah, now that you mention it those golf cart batteries are huge, and like four of them, or more, all wired together. Yeah, they're long to.
you could do voltage drop tests to see if you have a issue with a meter to save cutting

also you bought a group size 24 battery? as long as the miniimum requirements for the old girl are met by it that will work but it probably is smaller than your tray I would reckon lol. The group size 24 is common in small engine cars, like a 2003 toyota corolla i will just go out on a limb and assume with the inline 4 it has a 24 group size. 2004 nissan maxima might too i cant remember. i think saturn S series used it too? been a while.

I would say keep your SI alternator if you rebuilt it but if you ever wanted to upgrade I would skip straight to AD alternator before a CS. Similar price, better most ways.
 

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