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Spitfire Battery question

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N

number6

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A day ago I noticed the interior lights weren't going on with the headlight switch. After checking the usual suspects, I called it a day.
Next morning discovered I left headlight switch on and completely flat battery. I haven't had many battery problems, but the only other time this has
happened, it pooched the battery. I am going to try and charge it, and I think charging at low amperage is going to be better that hitting it with a high amp
(10 amps) charge. Slower and longer I think may be better for possibly saving the battery. Thoughts would be appreciated.
 
Depends on several things including the age and condition of the battery. You may get lucky but running a starting battery totally flat is often fatal.

How old is the battery? The warranty may give you at least partial relief. In my experience 'stupidity' (mine) did not void the warranty.
 
And...what type of battery is it?

Cheers
Tush
 
It's a generic replacement sealed unit. About 2 years old. This incident is the only catastrophic thing it's seen.
As far as warranty is concerned, I will have to check with the dealer, but it's probably a declining warranty, like tires.
 
Most battery warranties I have seen have a period of full replacement - usually at least 24 months, sometimes 36 months or more. After that it is pro-rata which is still worth looking into.
 
Just being flat overnight should probably be OK, as long as your charger will try to charge a completely flat battery. Many "smart" chargers won't charge a battery that is completely flat, they have to see some voltage before they will start to charge.

IMO any damage to the battery is already done, so the 10 amp charger is actually slightly more likely to recover it (because the open circuit voltage is higher).

As a side note, O'Reillys has really pulled back on battery warranties. I had a heated argument with them because they did not want to honor the warranty that was in effect when I bought my battery! It clearly said "72 months" right on the battery, but they tried to claim it was only warrantied for 2 years (because that was their current warranty on that model of battery). Needless to say, I won't be buying from them again unless I absolutely have to (which is how I wound up with one of their batteries in the first place).

The contrast to Costco is incredible. Although not written as a warranty, Costco will refund your entire purchase price any time you are not happy with your purchase. I returned a 4 year old battery that would no longer hold a charge (after being accidentally left flat all week) and the only charge for a new one was $5 because the core charge went up! I've not tried returning one after the advertised warranty expires, but I suspect the same rule would still apply.

Yet another side note, if your battery won't take a charge after being run flat, one of the commercially available "de-sulphators" may be able to save it.
https://www.superstreetonline.com/h...l/impp-1105-battery-desulfators-fact-fiction/
 
Taking Randall's advice I hit it with 10 amps for about 6 hours until the charger showed a green light. Started and drove it around
for about 45 minutes or so. So far ,so good. Will see how it is over the next week or so, I may have lucked out, but given the cold weather
upcoming we will see. I found the info on the battery recovery units helpful, not sure if the cost of one compares to just buying a new battery.
I think I am going to get one regardless, due to the number of cars I have at present. All my cars are located with put upon relatives and are far
enough away, they don't get run enough. I can justify buying a unit when multiple batteries are involved. Randall, Thank you.
Tom S
 
If you have cars that sit for a long time between driving have you looked into the Battery Tender (trickle charge) units.

I need to get one for my big truck that gets used every few months and usually needs charging before it will start.

David
 
I have looked into it, problem is 3 cars are stored in a barn and electricity is several hundred feet away.
Sister is not keen on running extension cord to the barn.
 
I take them out of the car, coat the terminals with grease, and leave them on the work bench.
 
I seem to have lucked out and the battery is holding a charge. The Gods are not smiling on me however as the
starter has just died. Turn key and it just spins, no engagement. So, now I am looking for a new starter.
 
number6 said:
...the battery is holding a charge... the starter has just died. Turn key and it just spins...
Click to expand...

Are you concluding that the battery is okay by simply measuring the voltage with a meter? If so, I wouldn't rush to replace the starter.

The better test of battery condition is a load tester. There are home versions or almost any auto parts place (e.g. O'Reillys, AutoZone) will do this for free.

A quick test you can do is to see what the battery voltage drops to when the starter is spinning.

Alternately you could try a jump from a running engine with a good battery.

There is obviously a lot more to a battery than just voltage - otherwise you could start the car with 8 D cells.
 
Indeed, a weak battery (or a poor connection in the starting circuit) can cause just that symptom. The Bendix drive on the starter relies on the motor getting a good solid jolt of current when the solenoid closes. If the current is limited by a weak battery (or bad connection), the starter may still spin but not have enough torque to throw the Bendix.
 
Randall, the symptom is just what you describe. So I went out and went through the rats nest. Checked the ground points, cleaned terminals and
gave it all a good looking over. Last thing I did was check cable to starter. Gave the cable a jiggle and the starter moved. Both bolts were loose.
So after 20 minutes of foul language and skinned knuckles, got it tightened back up. Tomorrow will tell if that was the only problem.
 
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