Question on battery/starter

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1977C20Silverado

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Backstory: Keep in mind the battery is a week old. My truck always starts easy, normally within a few seconds with 1 pump of the pedal. The other day it started just the same, even with it being below freezing. I drive about 5 minutes then it was parked for ~2 hours and when I tried starting it it wouldn’t. Cranked over for probably a minute in all. Then later that day I had jumper cables on it for probably 20 mins and it would only either click, or none of the electrical would work. Before I charged the battery, it said it had ~11 volts. Charged the battery and then it started with a hefty amount of starter fluid and my foot to the floor for probably a minute. Then the next day it started fine in the morning, then in the afternoon I had to jump it, but this time I only had the cables on for a minute or 2 and it started fine.
I don’t think it’s the alternator as it goes up to 14 volts as soon as it starts. Bad wiring? Im not very experienced with motors or electrical at all, as this is my first truck. I’m mostly concerned about the battery draining from starting fine to not cranking at all over 8 hours. If yall have any input to what it might be it’s appreciated.
 

Memaloose

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Start with the clamps on the battery posts. Make sure they're clean and tight. When things get cold and old they can contract and expand more. Also check grounds.
 

Doppleganger

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Probably a stupid idea, but have you had the battery tested? The first battery I bought for my truck (Interstate from Costco) acted similarly. I took the battery to a shop to be tested and they said it was reading 1 - possibly 2 bad cells. Thing wasn't a month old.
 

1977C20Silverado

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Probably a stupid idea, but have you had the battery tested? The first battery I bought for my truck (Interstate from Costco) acted similarly. I took the battery to a shop to be tested and they said it was reading 1 - possibly 2 bad cells. Thing wasn't a month old

Probably a stupid idea, but have you had the battery tested? The first battery I bought for my truck (Interstate from Costco) acted similarly. I took the battery to a shop to be tested and they said it was reading 1 - possibly 2 bad cells. Thing wasn't a month old.
I have not had the battery tested, and that’s what I thought it was. Funny thing is it’s also from Costco.
 

1977C20Silverado

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Start with the clamps on the battery posts. Make sure they're clean and tight. When things get cold and old they can contract and expand more. Also check grounds.
The terminals are on tight, i have not checked the grounds. It could possibly be that, as the ground is spliced and grounded in like 3 different spots. One of the previous owners rigged a lot of stuff up not very good.
 

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Every splice is resistance sometimes as much as .5 V. Clean it up, get battery and alternator tested. 11V is too low.

A fully charged battery should be in the area of 12.6V, alternator output around 14.5.
 

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A new battery isn't always a good battery.
Question- Why did you replace the battery a week ago?
 

Camar068

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If you don't know how old the battery cables are, I'd replace them. If it doesn't fix the issue, at least you know they are new....preventive thought.
 

1977C20Silverado

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A new battery isn't always a good battery.
Question- Why did you replace the battery a week ago?
The old battery was a few years old and wouldn’t hold charge. Had to jump it whenever I wanted to drive. Also update: I went to oreillys and they said the battery’s bad, the starter and alternator are good.
 

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Check the wire connections are tight at the battery and at the starter. You may have melted your cables a bit from long cranking.
Make sure your choke is working in your carburetor.
 

BRetty

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WhenI got my truck, I had constant electrical and starting problems. Eventually I learned the battery cables were old and oxidized/corroded, especially the exposed connections at the battery and starter terminals.

I pulled them and cut off the exposed portions, stripped them back to expose fresh copper wire, and hooked them into new lugs/terminals. Both Positive and Neg(ground) connections.

Flowing some solder into the stranded wires and any crimped lugs can only help, if you have the tools/skills. This may not solve all problems but it is a Very Good thing to give you a solid base for elec system.

Advice from this forum and (another) was crucial in pointing out the problem and the fix. So thanks!
 

Bloodhound1981

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A new battery isn't always a good battery.
Question- Why did you replace the battery a week ago?
That is for sure. I bought a new Diehard battery at Advance Auto last night. Brought it home, and it was reading 10.5 volts. Left it on the charger all night. Then it read exactly 12. But I literally watched on the multimeter as the volts quickly dropped back to 11 after unplugging the charger. At least the replacement I just got now seems ok.
 

JT58

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My truck had trouble starting after I got a brand new battery. Mainly after it warmed up. I had to replace the main cable (s) from the battery to the starter. I also had to route the cable down through the frame, it was poorly routed, connected to the top of the differential and moved up and down with the suspension. Someone did not know what they were doing when they routed the cable and also many other things I have had to fix on the truck.
 

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