Did I kill my jump pack, or my battery, or both?

Jackieboy

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Altenators are maintaining the charge, not for charging batteries from low to high. Buy a load tester and a decent charger. You will be glad you did.
 

Big Bart

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Some other thoughts

1) Deep cycle batteries are not strong starting batteries. In the the future you may want to go with AGM batteries. Deep cycle batteries are designed for being slowly drained and for their resilience to be drained down and charged dozens of times. Also you need to keep the water level up as they gas off and loose water. Low water in the battery cells can cause the battery voltage to drop.

2) The batteries under the hood are connected to each other all the time. So when you put a 2amp trickle charger on it is more like 1amp per battery. So going with a 3 amp, 6 amp, or 10 amp works better because when you split the amps between batteries you still have enough amps to charge effectively. Also when you load test them you need unhook them and test them Separately.

3) Once you have the batteries tested if they do not both test well it is recommended to replace as a pair. One good and one mediocre battery will give mediocre starting voltage and amps. So best to replace both rather than keeping a decent used one and a buying a new one.

4) As stated above when you test batteries make sure they are fully charged. But also that the test one battery at a time by unhooking it.

5) Also always make sure your battery terminals, stater solenoid connections (Both on the fender well and the starter, IDI’s have two.), starter, and block grounds are all clean and working.

6) If your jump pack is the large kind with a handle they use smaller agm batteries inside. You can open the case and get the battery size off it and order another to replace it. The batteries like your trucks batteries just loose capacity over time. I am not familiar with the new mini sized jump starters.

7) Also not all trickle chargers are created equally. Some actually maintain voltage by turning on and off and I believe changing charging frequency. Others claim to “maintain“ but just stay on all the time charging/over charging. Battery Tender brand is what I use for maintaining batteries.

8) As stated above almost all chargers say made after 1990 will not charge a battery that is less than say 6v.(Safety mechanism.) So as stated above having a old school charger can let you charge a good battery that is just low on power. Where as a modern one turn off charging with a fault code the battery is bad, even though it really is not. Keep your eye out at garage/estate sales.

9) A dead lead acid battery -
a) Often cannot not be charged.
b) Have been know to explode, crack, or catch on fire when rapid charging at say 10-50amps.
c) Often will suck up the majority of the power when jump starting making it near impossible to start a vehicle till it is replaced.

So be careful when working around batteries. Like all electricity you need to take precautions and respect it’s potential for danger.
1) Sulphuric acid burns our skin and clothes. Where gloves and eye protection When working on batteries.
2) Lead acid batteries off gas hydrogen which is flammable. It is recommended when charging these batteries the water caps are removed and they are charged in a well venilated area. That you turn off the charger before removing the cables to avoid a spark which can ignite the hydrogen.
3) Only use as much charging as needed. A battery that is 12.3 amps does not need a 50amp charge. A battery that is 8v and you are needing that vehicle to get to work or for testing. Then 50 amps might be appropriate. The slower you charge a battery the better. Charging a dead battery overnight at 2amp is better than 50amp for an hour.
 
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Selahdoor

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If a battery voltage is so low that the charger will not charge it.... Add in another battery. One that is high enough voltage that the charger will work. Then charge both at once until the low voltage one raises enough, to charge on it's own.
 

Max Mini

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Well, I couldn't get the batteries to take much and then I took them down to be tested. It seems they were pretty much shot. It's been about 2 years and with them sitting in the cold all this time without being used or put on a charger or removed, then with my running them down using my diesel heater continuously for two days, I think they were done. But... I also think I need an alternator (or something).

Both batteries are new. They take a charge very well, obviously. I took off the maintainer yesterday and had 13.5 volts. As soon as I tried to start - down to 12.2. I was able to get started, and was getting 13 while driving, but if I so much as plugged in the USB phone charger - WITH THE ENGINE RUNNING - voltage dropped instantly to 11.5.

Does that sound like alternator? All the cables have been checked by me and double checked by somebody smarter than me.
 

Max Mini

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Some other thoughts

1) Deep cycle batteries are not strong starting batteries. In the the future you may want to go with AGM batteries. Deep cycle batteries are designed for being slowly drained and for their resilience to be drained down and charged dozens of times. Also you need to keep the water level up as they gas off and loose water. Low water in the battery cells can cause the battery voltage to drop.
Thanks for all that, really helpful. I chose deep cycle, though, for exactly this reason. I live in the vehicle, and it's inevitable I will forget to unplug something. Sometimes I'm sitting for a long time in one spot, and I just don't always think to start up often enough. I have a lot of solar but often not a lot of sun, and I've killed enough AGMs to know I need that deep cycle resilience. I have honestly had no problems starting with them until now.
 

IDIBRONCO

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It seems they were pretty much shot. It's been about 2 years and with them sitting in the cold all this time without being used or put on a charger or removed, then with my running them down using my diesel heater continuously for two days, I think they were done.
Well that would certainly kill some batteries.
Both batteries are new. They take a charge very well, obviously. I took off the maintainer yesterday and had 13.5 volts. As soon as I tried to start - down to 12.2. I was able to get started, and was getting 13 while driving, but if I so much as plugged in the USB phone charger - WITH THE ENGINE RUNNING - voltage dropped instantly to 11.5.

Does that sound like alternator?
I would have to say yes. even the 13 volts while driving isn't high enough. They should be at 13.5+ volts while the engine is running. This would be a good excuse to do a 3G swap.
 

Big Bart

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Well, I couldn't get the batteries to take much and then I took them down to be tested. It seems they were pretty much shot. It's been about 2 years and with them sitting in the cold all this time without being used or put on a charger or removed, then with my running them down using my diesel heater continuously for two days, I think they were done. But... I also think I need an alternator (or something).

Both batteries are new. They take a charge very well, obviously. I took off the maintainer yesterday and had 13.5 volts. As soon as I tried to start - down to 12.2. I was able to get started, and was getting 13 while driving, but if I so much as plugged in the USB phone charger - WITH THE ENGINE RUNNING - voltage dropped instantly to 11.5.

Does that sound like alternator? All the cables have been checked by me and double checked by somebody smarter than me.
Could also be the external regulator if you have one. Not sure what they had in 91. (Internal or external.) My 88' has an external regulator and alternator. But when say the engine is at +2,000 rpm or more it should be charging as IDIBronco said at +13.5 volts.

You can take the alternator and regulator off and have them tested at a auto parts store or alternator rebuilder. If they do not have a newer tester they may not be able to test the regulator. But if the alternator passes and they cannot test the regulator, try a new regulator. The regulator determines the amount of charge the alternator is putting out.

If the alternator is bad, it is suggested your replace the external regulator at the same time too. Like others said a 3g upgrade will simplify and improve your charging system. The regulator is inside the alternator and it can charge at a higher amperage.

Well if you burned up several AGM's I get why the deep cycles. (AGM's can only be drained very low a couple dozen times. Deep Cycles can do it several dozen times.) But they are not as good for starting, can leak acid by the caps, and are more likely to corrode your battery terminals and cables. So stay on top of that. But sounds like they are more flexible with your use case.
 

Max Mini

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Altenators are maintaining the charge, not for charging batteries from low to high. Buy a load tester and a decent charger. You will be glad you did.
Right, what I'm saying is, the batteries are not holding the charge. I have a load tester AND a decent charger, thanks.
 

Big Bart

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I don't know what that means, unfortunately!!!
Think more modern/newer style alternator being put on a old truck. Bolts right in, just requires a little wiring kit and deleting/tying off some of the current wiring. It has a regulator inside it, so you do not need the external one on the fender well. (Or where ever your bus has it.). Your bus likely has a 70amp alternator give or take a few amps. A 3g charges at as much as 100amps as I recall. The 3g just needs two wires As I recall. Charge wire to the stater solenoid to charge the batteries. A wire to the warning lamp to energize the alternator so it can charge. You do not need the field, ground, or stator wires as I recall. You can do a search for more info. Simplifies the charging system while making more power.
 

The_Josh_Bear

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I didn't see the voltage state for each battery individually, just the pair. You have to test them individually as you may have one health battery at 12.5v standing and the other with a bad cell at 11.0v and the bad one is just a giant resistor when hooked together and starting.

If you do have a bad battery you could still start on the one good one with a health system and use the jump pack too if need be. Just disconnect the bad battery and wrap up the positive terminal so it doesn't short.

Another note, those jump packs can work way better than you'd think, I have 2 and they are pretty stellar.
1. Li-ion cells suck in the cold, make sure the pack is warm-ish before jumping.
2. Don't hook up to the negative battery cable on the bus. Hook up the negative clamp to the frame/hood latch and positive to the terminal on the passenger side battery with the hot lead that goes down to the starter.
3. 80% standing for being out all winter is fine for Li-Ion. They will naturally loose charge down to about there and stabilize. I guess that's not super healthy for them to sit at 100% but it's job is to be ready so what are ya gonna do? :)

Hope that helps some. I've been able to get many cars started by clamping the ground at the hood latch when clamping at the negative terminal wouldn't go.

Ha, edit! My phone left out the last like 10 messages so...whoops.

3g upgrade for the win! It's pretty minor wiring, just Google 3G upgrade Ford and you'll get a few good hits about it.
You can get used 3G's at wrecking yards for fairly cheap or grab you a new one. One of the best upgrades I've ever done.
Oh and they are 130a BTW. You will need to make sure the case is 2 mounting points at 180° apart like your current alt. (Unless you have a serpentine belt, that may be different).

Happy wrenching!
 
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