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1969 Mustang Coupe Project Car
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Ok I went out to start the ride today and the new stereo and clock have drained the battery. So I jump started the car and let it run for about 30 mins. This made me start to think about a couple questions.

1 When you have an 80 alt, does the alt put as much current as available into the now dead battey? If so how long would a full charge take?

2 Is it better to charge a warm battery or a cold one?

3 I want to put a battery switch in the car but I want the I have some clearance issues with the hood. Do they make a inline switch or one for the front connection type batteries?

Thanks guys
Regards
Mark:thumbup:
 

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Start those projects someday
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The alt wont put out 80 amps while charging the battery. That is its rated capacity to charge under load. It varies quite a bit depending on what type battery, and how it takes a charge. A dead battery should be slow charged. Its not a good idea to charge the battery from the vehicle charging system. Its not designed to charge a batt, just maintain it. You should always charge it from an external battery charger. The alt will overheat and burn out the diodes.

A slow charge will slowly heat the battery while it charges.

Are you looking for a switch that mounts directly to the battery? Have you looked at a RV type cut off switch (rotary)?
 

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You have the stereo wired wrong or your battery is history. No way should that have enough parasitic drain to take a healthy battery down in weeks or months, let alone overnight. The only wire that should have drain is the keep alive for the settings memory. All the rest, like amps or the main power feed to the stereo should be run through a key on power source.
And 2 many is right, the alternator will put out too much. But at isdle isn't really putting out anywhere near 80 amps. The alternator is actually made to carry the work load during running and the battery is for starting the engine and absorbing voltage spikes from the charging system.
 

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1969 Mustang Coupe Project Car
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Discussion Starter #4
Has any of you tried the solar battery panels for keeping your ride charged if it sits for long periods? I've seen them at Harbor Freight and Tools and they were on sale for 9.00 the last time I went. It's just a trickle charge I know.

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Mark:thumbup:
 

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My personal opinion on those is that if you have a properly operating system you shouldn't need one. I have a lot of cars and they sit for months at a time and I do expect then to start even after 6 months. I know the're popular among RVers but I dont use them in my RVs. There are a lot of electrical systems in an RV , that is why they use the cut off switches. If there is a substantial draw I want to find it. One the other hand if it will solve the problem then I can see where it would be useful.
 

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drain

Doc here:pimp:

HAPPY THANKSGIVING!

The Stereo and Clock SHOULD not have drained the battery (unless it sat for like a year..)

The most common Cause for the drain is bad regulator or diodes. Check the Alternator. A simple test is just disconnect the alternator before you store it NEXT, If when you return it's still full charge, you have found the problem!

Also, An alternator Was not designed to deep charge a battery. It's sole function is to support the running system and return a surface charge only.

Should the battery seem to "Spring" back to life after a short run..It's only because it's surface charge is restored, But each time you tax the battery, It draws a little more on the deep charge until that is depleted,: result: over time is a dead battery.

You should charge your battery 4 to 6 hours at about 10 amps to bring it back up. Chemical reaction within the battery will warm it up during charge, but if you live in a really cold climate it's best to Store/ charge it in a warm environment.. Here in California, It makes no difference.

If you store it for a long period of time, Warm is better If you have really cold winters.. place it on a non conductive Surface (Wood, Glass, plastic, rubber etc..) If you let it sit on cold concrete it will go dead.

If you use a Battery Disconnect switch, Be advised you may have Computer and Radio memory Circuits that you may want to diode isolate, Fuse at 1 amp, and bypass the Disconnect. Each time you use the disconnect the computer it will lose data, the presets on the radio will go away, and the clock will stop...Some Computers have a "LEARN" mode that can take up to 10 ignition cycles to program... It may run badly during that phase, flash codes etc...Plus you have to reset everything..

I used one on my 80 Vette for anti Theft, and it was a hassle. Lojack was a far better investment! If you are going to store it for long periods (10 months a year..) then it's a good thing to have..and having one IS a good safety issue, you can pull it in case of Massive Short . But to use it on a regular basis is a hassle.

The best way is to address the drain issue, If it is the diodes on the alternator, It can have other repercussions .. 1/4 of the charge cycle is AC..

That Can damage Semiconductor devices, Computers, Expensive CD/Radios and digi clocks, Engine control modules..Solid State devices won't tolerate a lot of AC abuse at the power input..They heat twice as high and fast causing thermal shut down sometimes permanent shutdown.

I would eliminate or repair the alternator, and track down the sources of drain other than just disconnecting them..might save you headaches down the road!

HAPPY HOLIDAYS!

Doc :pimp:
 

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Doc, Just curious if you have ever read anything on the battery on the concrete floor thing. We always followed that religiously and had wood to set them on. Several years ago I was to a clinic that Interstate Batterys put on (and a very good one too). Anyway the subject came up about setting batterys on concrete and their technician said it was an old wives tale. He said maybe the cold might make a small difference but nothing in concrete can harm a battery.
I was gone for 1 1/2 years over 2 winters from my cabin in Alaska and took a Megatron off the shop floor and started my truck right up. Keep in mind it is -30 for weeks at a time with maybe some dips to -45 outside. So I have to wonder if there is any validity to the aleged negative affects of setting a battery on concrete.
 

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In theory (and educated guess), a battery placed on concrete should outlast a battery placed on something/somewhere warm. The colder a chemical is the slower it will react, hence less wear on the battery internals over longterm storage. On the flip side though, if you wanted to use the battery within a short period of time (as in a retail outlet selling a battery to a consumer), keeping it off of concrete an in an area that is warm would keep the chemical reaction in the battery going at a better pace, ie the surface charge would remain higher and the battery purchased "off the shelf" would have a healthy charge in it.

Marc
 

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Mark, I have several of the red solar panels from HF & as long as the battery is a good one, they work fine. They won't recharge one that's down, but they seem to keep them from discharging when they sit for a while. The only problem I've had is from bad lighter plugs/circuits in the cars.
 

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Floor Storage

Doc here::pimp:

HAPPY THANKSGIVING!

Willowbilly3,

Never read anything about it...

I was told that, "Eons and Eons" ago, by (Even back then) oldie Wrencher 's (Who MAY have had Olde Wives Telling tales..:D LOL ) in their field, and just Took it as a logical answer..

Besides it wasn't a big thing to put a piece of wood under one...(But battery Cases were also made out of Tar And other stuff similar to but not plastic, different than today..may have made some kind of a difference, I don't know..)

And second, everyone I ever stored on the garage floor went dead or low after a time..

Co~ winkey Dink, or bad luck?

I don't know , but, I always put wood under them .. They seem to fare better..and, At the very least the wood will soak up any spilled or leaked acid as opposed to having it make "Trails" all over the floor...

HAPPY HOLIDAYS!

Doc :pimp:
 

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Well, I still put them on wood when I leave them on the cement floor too, usually. Just an old habit and seems like the right thing to do. I was just looking for any scientific evidence that there was anything to it.
 

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OK, here is the story I've gotten from some off-grid people (the ones who don't have access to a power line and live off batteries).
The old-style rubber cases were slightly porous and actually became a tiny bit conductive and leaked a little trickle current right through the case. Hence, a wood block stoped that. Since stored batteries often sat for months, that tiny leakage was enough to make the battery go flat.
The newer plastic cases have no such problem and can safely be stored on a concrete floor for long periods.
With either battery, remember cold reduces capacity. A battery stored outside in the cold should be allowed to warm up before being used.
I never trust a battery that has sat in a car for over a couple of months. Both my Cadillac and my CJ will drain the battery flat in 3 months from legitimate "keep alive" parasitic loads.
 
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