Fox Concerns leaving battery connected when car sits a lot?

91GTstroked

15 Year Member
Jun 14, 2007
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Hey guys,

I recently bought a shop and have my 03 cobra there now on a trickle charger.

I plan on bringing my 90 coupe there soon and doing the same thing. But I'm worried about doing it. The car is old, has a wire tuck and battery in the truck.

I guess I'm being paranoid of possibly an electrically fire, being the car is modified and old wiring.

Thoughts?
 
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I’ve had cars on trickle chargers for over 10 years that were only used on occasion and never had any issues. As a matter of fact the batteries lasted perfectly for a ten year period.
I don’t see a Problem with that as long as you use a real, great quality device and not a cheapo like ones for 10 bucks at certain stores.
do yourself a favor and buy a good quality and reputable one and you will be fine.
I always use “battery tender” brand. The Junior models. They are great and have safety features built in to avoid over charging, overheating, etc.
 

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I disagree. 32 year old wiring (depending on the build date), a wire tuck with moved battery, damn insidious rodents, and a car that it does not hurt to disconnect the battery on makes a battery quick disconnect an excellent option. I’d use one on both Mustangs if they go weeks without road time.

You can still use a battery minder/tender on a disconnected battery and worry less about a fire. But I have never had a disconnected battery go flat, and my battery tender is still new in the package.
 
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^^^ I agree ^^^
But I will add that brand x out in my garage has a batt tender on it and has been there for probably 8-10 years and only replaced the 6 volt battery last year. Rarely driven cause I hate it,
 
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That’s great for a six volt battery! Unless they updated the designs, the ones they sold at the parts stores, (when I was last behind the counter), were lucky to last two summers.
Disconnected, or disconnected with a battery tender, a charged battery kept from engine heat and vibration can last a very long time compared to a daily driver’s battery. 8 years on 60 month batteries in my Olds has been easy, and the last one in my Mustang died at almost exactly 10 years iirc.
 
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Normally, when the car has been in the storage unit I just disconnected the negative cable and the battery would stay in the 12.20-12.30 range. I may do that again.

This battery tender I've had for many years for the cobra. I just bought a newer version for the other car.
 

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Any of our cars that no longer have emissions check for inspection (monitors via OBDII), I disconnect the neutral, when sitting. Then periodically or in the spring, I tune up the battery with a tender for a day or 2. Working for me.
 
Typically with long term storage, I remove the battery and put it on a battery tender. I don't even run the tender 24-7, but let it sit a few days, and then remove it and let the battery sit 1-2 months without touching it. Then i'll toss the tender back on it.
 
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Thanks for the feedback everyone. I brought the car to the shop.

Just disconnected the negative cable for now.
 

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Nice car. I have had a 2 bank Battery Tender in my garage for as long as I have owned my house. Going on 11 years now. One bank stays on my 87 FoxBody, Optima Redtop in engine compartment, the other bounces back and forth between mine and my daughters quads. Knock on wood, never any issues.
 
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If in question, I’d prob leave the battery disconnected. Just to be safe.

I put a disconnect switch in mine.. it makes it easy since my battery is in a box in the trunk. I use it during the winter and when doing electrical work. I also use a battery tender jr In the winter. It’s wired with a hookup outside my box.
 
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I may be the outlier. But over the last 15 years ive had 3-4 different sports cars and have either just disconnected the battery or did nothing over the winter. Over that time I have never had to replace a battery and have only had had to jump/charge a battery 3-4 times. Guess I am to the point now where why bother with the extra step and equipment and hassle. Batteries in general are a 5-7 year item and when they go they go.
 
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Whats odd to is I have a boat that I dont anything with either charges right up every spring and batteries are 8 years old. Golf cart batteries which charge all the time I have, die like clock work at 5 years. Like I said earlier Im not monkeying with this, added equipment and utility cost for really no reason in my mind.
 
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I agree. I’ve had the battery out of my car now for 2 years. Every 6-8 months or so I toss it on the battery tender and it barely take anything before it goes into float mode. I bet it would be perfectly fine without a charge all winter just disconnected.

I’ve also gotten in the habit of proactively replacing them (mostly on my DDs) anyway around year 5. Just easier than dealing with a dead battery when I need the car the most. I had one die on my on vacation. What a pita and huge hassle.
 
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I like my red guarded switch and disconnect relay. It makes me feel tough when everything jumps to life before turning the key. :shrug:

Not the best method for cars that still rely on adaptive strategies.
 
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I dont ever bother disconnecting my battery, when the car is stored for winter I will start it up once every month or so and let it run up to operating temperature.
 
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I dont ever bother disconnecting my battery, when the car is stored for winter I will start it up once every month or so and let it run up to operating temperature.
Used to do that too. I live where its cold and after reading have stopped that too. Guess its not good to start here and there and let it sit, moisture accumulates in the oil, exhaust, storage space etc.
 
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