850cca megatron dead?

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Central NY
2015:
Realized the interstate is 7.5 years old in service. Had issues (no start) and when I took it back to the dealer to check it out, they said it was shot. After reading on BITOG about batteries, charging etc, I sent my Craftsman charger packing and got a new one (Pro-Logix PL2320) and she hasn't had an issue since....

Today:
so I was working on the truck today, only the hood was open (small bulb).
Then I drove 15 miles, half highway and half city, to the hardware store. Came home, worked on the truck again for 30 minutes and left the key in the ON position. No radio or lights on and just the fan on the lowest speed.

Went to start the truck and it wouldn't turn over.
Hooked up the pro logix charger and put on 20A (no start feature) and it said 14% and less than 12v (this was connected directly to the posts since my usual ground wasn't working).


I started it right up, moved her and then shut her down.
Reconnected with negative on proper ground.
said 84% and just over 12v and after ten minutes she's at 87% charging at 20a.


Is this thing shot????
can't believe it went dead so quickly.
thanks
 
I'd check the fluid and charge it at 2 amps overnight, assuming it's a smart charger. 8+yrs, it's probably about done, keep the jumper cables in it.
 
It doesn't take a lot to damage a lead acid battery, and remember that alternators don't properly and completely charge a battery. A high rate charge also forces an over potential that isn't always great for the battery...
 
Nope, not dead, capacity compromised. How compromised, unknown.

The blower motor on low is still about 4 to 8 amps.

Your Key being on could cause significantly more drain than you believe

How much you drove is fairly irrelevant without knowing what voltages your vehicles voltage regulator allowed in that time. The alternator is not a magical instant battery charger

Leave your prologix on 20 amps, when it flashes the green light indicating full charge, load batteries with headlights until voltage drops below 12.8, and restart charger on next amperage lowest setting. Lather rinse repeat.

A 2 amp charge overnight will not get it anywhere near full, its got to spend many hours at 14.4 to 14.7 to get near 100%

Do Not believe the % charged on the prologix. it is entirely voltage based Guestimating. Voltage on a recently charged or discharged battery is not representative of actual state of charge. The % is meaningless most of the time except when the battery has been sitting without charging or discharging for a few, to many hours.

Surface charge can take 24 hours to settle and the percentage will read high even if the battery is not fully charged or even anywhere near it.
 
I have a mower battery acting the same way but limping it till season ends in probably 3 weeks. I carry a big jump pack in my Xttera to help friends and family as Nissans theft system hates jumping etc and a smaller pack in the car. Easier than trying to get someone to help one out and I never seem to have issues when theres is someone around to help.
Your probably going to have to part with a Franklin and get a new battery or find a fairly new one at a salvage yard. My last truck battery was a 1 year old Interstate for $35
WRC68 has the charging attempts pretty well summed up. GL
 
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In 2015 you started having issues with a 7-1/2 year old battery, and then babied it along until now, so you're at well over 8 years old. Correct?

Buy a new battery and be done with it.

Originally Posted By: rsylvstr

Is this thing shot????
can't believe it went dead so quickly.
thanks


Seriously? It's a battery that's at least 8 years old, possibly more. Yes, they eventually fail completely and trying to revive them is a waste of time.
 
Originally Posted By: wrcsixeight
Nope, not dead, capacity compromised. How compromised, unknown.

The blower motor on low is still about 4 to 8 amps.

Your Key being on could cause significantly more drain than you believe

How much you drove is fairly irrelevant without knowing what voltages your vehicles voltage regulator allowed in that time. The alternator is not a magical instant battery charger

Leave your prologix on 20 amps, when it flashes the green light indicating full charge, load batteries with headlights until voltage drops below 12.8, and restart charger on next amperage lowest setting. Lather rinse repeat.

A 2 amp charge overnight will not get it anywhere near full, its got to spend many hours at 14.4 to 14.7 to get near 100%

Do Not believe the % charged on the prologix. it is entirely voltage based Guestimating. Voltage on a recently charged or discharged battery is not representative of actual state of charge. The % is meaningless most of the time except when the battery has been sitting without charging or discharging for a few, to many hours.

Surface charge can take 24 hours to settle and the percentage will read high even if the battery is not fully charged or even anywhere near it.



I'm slow when it comes to anything electrical.

Was fully charged in 20a overnight.

Turned on lights and fan, ProLogix read 8% and 11.8v. I know that's not that accurate.
I then shut the key off and it went to 63% and 12.4.
Does that mean anything?

Now charging at 10a.

I thought I read on here that these ProLogix are set and forget and cycle to avoid all this?
Thanks for the patience. Just trying to learn.
 
Back to 100%
Turned lights on and it drops 1% every second.
I know that's not accurate but is that "normal?"
Stopped at 35% and 12.1

Started it up to move her and it went to 54% after I shut it off.
Now charging at 2a
 
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LOL!!

You're seriously wasting a lot of time and effort on a lost cause.
 
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The headlamps are about a 15 amp load, in addition to whatever the key to ON, not start load also is.

It does appear the battery is dropping voltage far too quickly under those loads.

At 7.5 years the battery owes you nothing. it will continue to start your vehicle until that really cold morning when it is most inconvenient for you to jumpstart it and then to try and replace it.

The prologix is a good enough battery charger, but no charger is going to restore lost plate material, and hardened sulfation is pretty much a given at 7.5 years, and No the magical pulse desulfation chargers do not work 98% of the time despite the claims of those that bought them.

The 'lather rinse repeat' restarting of charger is simply to allow that last 2 to 8% of charge to get into the battery. Hopefully it will hold 14.x volts for long enough for this to occur. Loading the battery until voltage falls is simply to trick the charger into thinking the battery is depleted so it will seek 14.x volts again.

All 'smart' chargers will cut off absorption voltage prematurely as it is safer to undercharge, than to overcharge and lawyers love to hover greedily. 92% charged is 'good enough' but 100% is much much better, and can take a few more hours at absorption voltage.

A hydrometer will reveal this time and again. OTC4619 cut paste search.

Getting that last 2 to 8% in on a healthy battery will allow it to stay healthier for longer.

It is quite difficult to get that last 2 to 8% in on a deeply discharged battery at less than full health it takes a long time at absorption voltage.

YOu can lather rinse and repeat, until it is restored to its maximum remaining capacity, but that capacity might only be 20% of when this battery was new, but this amount of capacity will likely fail you on the cold morning when most inconvenient to deal with.

So plan accordingly, and start searching out some battery specials as your megatron is giving you all the warning signs and at 7.5 years, owes you nothing.

Regularly using the prologix overnight will extend the life of the new battery as all lead acid batteries want to spend their whole life at 100% charged, and anything less is detrimental to some degree.

If you do a bunch of radio listening or other battery depleting activities with engine off, then the prologix overnight becomes much more beneficial, and a 2 amp charge rate would be sufficient to top it up, but sometimes higher charge rates are more beneficial, if recharge time is limited or 2 amps is simply unable to achieve 14.5 volts no matter how long it is applied.
 
Cool thread IMO
smile.gif


Appreciate it.
 
She's dead.
Turned over slowly one last time yesterday.
Tried charging and received all sorts of craziness on the readout.
Popped the caps and three cells are fizzing and "dirty" looking water.

Off to ChinaMart
 
Love it. LOL.

Battery
8/16 manufactured.
ProLogix says it is 60% and 12.3.
2a trickle overnight to kick things off right.
 
Originally Posted By: rsylvstr
She's dead. t


It took you a month to accept it. Your battery should have been replaced a year ago.
 
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