Replacing reversed polarity battery

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Megabeccatron
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Replacing reversed polarity battery

Unread post by Megabeccatron » Sun Oct 15, 2017 3:32 pm

Ok, I am totally new to cars and forums. It is best to assume I truely know nothing. I will probably get terms very wrong. So here is my first question post... And it's weird.
I bought a '62 coup. Just started getting into it. Noticed that the battery currently installed has the polarity reversed. Let me clarify... Everything is hooked up "correctly", the car runs, but when you look at the battery the terminal marked positive goes to the ground, and the terminal marked negative goes to everything else.
I know I need to replace the battery. I am wondering if when I do that, if it could potentially damage anything?
My ignorance is making wonder if a battery with reversed polarity will put out less "juice"? So when I put on a correct battery, could it then send more power through the system than it is used to and mess a bunch of stuff up?
If it's a dumb question just say so... I promise my feels will not get hurt.
Last edited by Megabeccatron on Sun Oct 15, 2017 3:58 pm, edited 1 time in total.

skipvair
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Re: Replacing reversed polarity battery

Unread post by skipvair » Sun Oct 15, 2017 3:36 pm

Try polarizing the generator. I haven't done it in years, so look up the exact procedures


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Jim in Wis.
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Re: Replacing reversed polarity battery

Unread post by Jim in Wis. » Sun Oct 15, 2017 3:49 pm

I would put the battery cables on the correct terminals and try running it. You can't hurt anything, and there's a good chance the battery will be ok. Some things work just fine with the polarity reversed, others don't. Lots of cars have had this happen - a modern car with a computer would probably be a disaster, but a nice simple electrical system like on a Corvair doesn't have much that could be damaged. The radio might not like it and the generating system could have some problems. Polarizing the generator is just a matter of momentarily energizing the field coil with the correct polarity. It probably won't be necessary.

Megabeccatron
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Re: Replacing reversed polarity battery

Unread post by Megabeccatron » Sun Oct 15, 2017 3:51 pm

It has been converted to an alternator. This was done before I got the car, so if there are special considerations to how it should have been done, I have no history.

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Re: Replacing reversed polarity battery

Unread post by bbodie52 » Sun Oct 15, 2017 4:00 pm

Can you post some photographs of your engine compartment? Is hard to believe that the battery is truly connected so that the voltage is reversed. The diodes in an alternator would not last long if the polarity of the battery was reversed! Have you confirmed this by tracing the cable connections? The thick cable from the positive battery terminal should be routed directly to the starter motor solenoid. The thinner wire should be connected to the voltage regulator and to the alternator.

The original Corvair alternator that was installed in Corvairs beginning in 1965 utilized an external voltage regulator. Later GM alternator designs made use of an internal solid-state voltage regulator that were integrated into the alternator housing. Does your alternator connect to an external voltage regulator? Again, some photographs of your engine compartment would be useful.

Are you familiar with reading and interpreting electrical schematics and wiring diagrams? I have prepared a number of combined wiring diagrams that combines three pages of wiring diagrams in the shop manuals into a single diagram that can be enlarged and traced from end-to-end to help with tracing individual electrical circuits from one into the other, without having to flip pages and figure out where the circuit left off on one page and picks up on the next. I have also included modifications to some of these diagrams to show the correct wiring configuration when converting an early Corvair from a generator to an alternator (when using an alternator with an external voltage regulator). These diagrams may be helpful to you, and if you need further explanation in reading them I can assist you with that effort.

CORVAIR COMBINED WIRING SCHEMATIC DIAGRAMS
:link: viewtopic.php?f=225&t=12968

I strongly recommend that you do not start switching wires around or reversing battery polarity connections until you thoroughly understand what you are doing. Randomly changing wiring without understanding could possibly result in an electrical fire or in damaged electrical components within the car. Again, photographs of your engine compartment that are sharp and detailed would be helpful.

If the voltage of your battery was truly reversed I would think that it would make short life of the diodes in the alternator. American cars, and most other cars in the world are designed for a negative ground that is connected to the car chassis. The positive battery terminal must be connected to provide voltage that is fused and switched throughout the car.

The negative cable that is connected to the negative battery terminal should be bolted to BOTH the car chassis AND to the engine. (The engine and transaxle are suspended from the car chassis at three points. The two front mounts connect to a bracket that is attached to the front of the transmission. The rear mount is in the center-rear of the engine compartment. All three mounts are rubber so they tend to not only isolate engine vibration from the car chassis, but they also isolate the transaxle and engine electrically from the car chassis (which serves as a common ground throughout the car).

Check your battery ground to ensure that the ground cable is attached to BOTH the car chassis AND the engine, as shown in the diagrams below. The engine and transaxle are physically and electrically isolated from the car chassis because of the three rubber engine mounts. If a single battery ground cable is only connected to the chassis, the starter, generator/alternator and engine may not be adequately grounded. This could cause starter or charging system problems.

Image

The information below pertains to the Interstate battery line that fits the limited, odd sized battery box area in Early Model Corvairs. Feedback I've heard from buyers of the Interstate battery line seems to indicate that this brand is a quality product.
If you need a new battery, the odd size and shape of the EM battery box might confuse things a bit. Clark's charges quite a bit for a battery that is similar in appearance to the originals...

Part number C12541: 61-64 CAR & 61-65 FC SCRIPT BATTERY *1960 SEE C13056

Weight: 30 lbs 0 oz
Catalog Pages(s): 79
Price: $ 264.55


But there are some other choices that will fit, will provide better service, are locally available, and cost less. The battery information below has proven to provide a good fit in the standard early model Corvair (1961-1964) battery box.

:idea: Here is a battery tip for early model Corvairs like yours that may help you to get an affordable battery for your early Corvair. Be sure to compare the battery dimensions with the available battery space in your Corvair. The dealer catalogs and references are unlikely to tell them if this battery will fit your car...
freedo wrote:In my EM i ran a Interstate 51 battery, might have been a 51R can't remember off the top of my head. its a honda civic batter, its small so it fits in there, but it doesnt fill in the whole space. worked perfectly fine for me. cranked everytime, never let me down
MEGA-TRON 51-R AUTOMOTIVE BATTERY 75 MONTHS 500 CCA

Get long life and premium performance with Interstate Batteries' Mega-Tron 51R. With 24-months free replacement and five-year performance, this 500 CCA automotive battery will meet or exceed your vehicle's starting requirements in any hot to moderate climate.

Sugg Retail Price: $107.95
List Price: $129.95
Dealer prices will vary

Product ID: MT-51R
Amps: 625
Cranking Amps: 625
Cold Cranking Amps: 500
Voltage: 12
Termination: A
Weight: 27.9
Width: 5.13
Length: 9.38
Height: 8.88
Plates: 24
WET/DRY: W


:wrench: Here is some additional info on the use of the Interstate 51 battery...
freedo wrote:you have to make sure your tie down is tight or it will slide side to side. or you can make some plastic pieces to wedge it into shape. but interstate are strong good batteries. when i blew the motor up i had the lights on and the interior light on for almost a hour and when i went to start it up the next day it cranked right over
It appears that the only difference between the Interstate MT-51R and the MT-51 is the location of the positive and negative battery terminals...

MEGA-TRON 51-R AUTOMOTIVE BATTERY 75 MONTHS 500 CCA
:link: https://www.interstatebatteries.com/pro ... oryid=true
Image

MEGA-TRON 51 AUTOMOTIVE BATTERY FIVE-YEAR PERFORMANCE 500 CCA
:link: https://www.interstatebatteries.com/pro ... oryid=true
Image

The correct battery appears to be the Interstate MT-51R, which places the positive terminal correctly on the right when the battery is placed in the battery area with the terminals facing the engine.
Brad Bodie
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Image 1966 Corvair Corsa Convertible

Megabeccatron
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Re: Replacing reversed polarity battery

Unread post by Megabeccatron » Sun Oct 15, 2017 4:09 pm

Is that picture clear enough?

It seems that the battery itself is reversed. When I read about it, it seems some tractors use a battery thatvthe polarity has been reversed on? I did get this car from a farm. :P

It seems like I just need to get a new battery. I am have some electrical issues... I have no idea yet if they are related to the current condition of the battery yet. I figured the first step was replacing it but I'm wondering if just changing it out I could cause other problems.
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Megabeccatron
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Re: Replacing reversed polarity battery

Unread post by Megabeccatron » Sun Oct 15, 2017 4:12 pm

Spark comes from what is labled negative onbtjis battery

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Re: Replacing reversed polarity battery

Unread post by Megabeccatron » Sun Oct 15, 2017 4:16 pm

From your post bbodie, it looks like I need to fix the groud as well as some other stuff and try to trace back the wiring to make sure it's all correct. This is definitely on the list. Thank you for the resources! I just figured getting a correctly polarized battery is step #1.

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Re: Replacing reversed polarity battery

Unread post by bbodie52 » Sun Oct 15, 2017 4:38 pm

I must admit, this Corvair has me worried. I cannot see all of the alternator, but what I can see appears to be a strange configuration in the way that is wired and in the way that it is mounted. It does appear the photograph that your car has been reconfigured and "jury rigged". I can't tell from this photograph if there is an external voltage regulator. Does the black cable on the battery negative terminal connect directly to the starter solenoid? The battery connection cable that ties to the solenoid is supposed to be the heavy cable that connects to the positive battery terminal. The starter housing is supposed to be grounded to the engine and then tied via another heavy cable to the battery negative terminal. It does appear in your photograph that your Corvair has been reconfigured somehow for a positive ground! I cannot tell from this single photograph what type of alternator has been installed on your Corvair.
:dontknow:
1965-1969 Corvair Engine Compartment Wiring Harness Starter Connections.jpg
1965-1969 Corvair Engine Compartment Wiring Harness Starter Connections.jpg (80.88 KiB) Viewed 284 times
Brad Bodie
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Image 1966 Corvair Corsa Convertible

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Re: Replacing reversed polarity battery

Unread post by Megabeccatron » Sun Oct 15, 2017 4:56 pm

It is internally regulated.
If I am understanding correctly... Things seem to be wired "correctly" but the battery is backwards. What is labeled positive is actually the negative and what is labled negative is actually positive.As if someone completely drained the battery and then hooked it up to a charger backwards.

I don't plan on solving this by myself. Maybe it's best if I have someone who knows more look at it and then revisit the issue.

Thank you!

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Re: Replacing reversed polarity battery

Unread post by bbodie52 » Mon Oct 16, 2017 5:15 am

I grew up in a negative ground automotive world. I always thought that if I touched a positive ground car it would be fatal! :doh:

Seriously though...
Reverse Polarity.jpg
The battery markings are correct. You cannot reverse the internal polarity by draining it and then hooking it up backwards. Your Corvair was apparently reversed to a positive ground system to accommodate a positive ground alternator that was designed for a tractor.
Polarity makes no difference at all to a car. Several minor differences include the coil terminals, which on positive ground cars are reversed (positive and negative ground coils are wound in different directions). The negative wire attaches to the power supply and the positive wire goes to the distributor/points. Light bulbs will work in either polarity, as will starters, relays, and heater blower motors. The radio will not; they are polarity specific.

With the advent of the electronic age, the automotive field embraced solid-state voltage regulators, electronic ignition, transistor radios, and other upgrades. Parts such as transistors and diodes were designed with negative ground, which became standardized. Positive-ground vehicles gradually became a thing of the past.
:link: http://www.restore-an-old-car.com/posit ... -cars.html

Car starter motors, light bulbs, fuses, switches, horns, etc. are not usually sensitive to DC polarity reversal. Electronic components are. Diodes and transistors will fail if polarity is reversed.

Most starters are a universal motor, meaning the magnets inside are actually electromagnets that are energized by the current from the battery. Reversing the input polarity will reverse the electromagnets as well as the armature, resulting in the motor spinning the same direction with either polarity applied.

You appear to have an odd alternator that was adapted for use in your Corvair (by a farm mechanic?) Alternators use diodes and often solid atate electronic voltage regulators. I'm guessing that some type of positive ground farm implement alternator was adapted for use in your Corvair because some farmer had one to use for the charging system modification project. The needs of that alternator (positive ground) may have been the deciding factor in determining which way the battery was connected. Is there a radio in the car? Was the ignition coil reversed? There is not much in the way of solid state electronic devices and polarity sensitive devices in a vintage Corvair.

If you wanted to correct this unique, reverse engineered Corvair by reversing the battery back to the original factory configuration, I suspect you will need a new, negative ground alternator and would need to change the wiring to match. You also might need to check the radio and ignition coil wiring. :tongue:
Brad Bodie
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Rdhog99
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Re: Replacing reversed polarity battery

Unread post by Rdhog99 » Tue Oct 17, 2017 9:14 pm

Another thing to check is that the battery is putting out positive from the positive terminal. It is possible although rare that the battery could of been charged up backwards reversing the battery output. This can happen if the battery was completely dead and a charger connected backwards. The battery would be damaged but could operated the car like this for a while.

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Re: Replacing reversed polarity battery

Unread post by azdave » Wed Oct 18, 2017 6:14 am

bbodie52 wrote:
Mon Oct 16, 2017 5:15 am
You cannot reverse the internal polarity by draining it and then hooking it up backwards.
Actually, it is possible to charge a lead-acid battery backwards. Not that it works as well being reversed but it can be done.

My friend did it in his 60's era Corvette because he let it go completely flat after leaving a light on for a month. He then hooked up the clamps wrong when he used a battery charger.
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Re: Replacing reversed polarity battery

Unread post by azdave » Wed Oct 18, 2017 6:15 am

azdave wrote:
Wed Oct 18, 2017 6:14 am
bbodie52 wrote:
Mon Oct 16, 2017 5:15 am
You cannot reverse the internal polarity by draining it and then hooking it up backwards.
Agreed with Rdhog99. It is possible to charge a lead-acid battery backwards. Not that it works as well being reversed but it can be done.

My friend did it in his 60's era Corvette because he let it go completely flat after leaving a light on for a month. He then hooked up the clamps wrong when he used a battery charger.
Dave W. located in Gilbert, AZ
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toro V8
65 Monza 455 Toro V8
65 Monza 4DR 140 PG w/factory A/C
65 Monza 4DR EJ20T w/5-speed

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Re: Replacing reversed polarity battery

Unread post by azdave » Wed Oct 18, 2017 6:16 am

bbodie52 wrote:
Mon Oct 16, 2017 5:15 am
You cannot reverse the internal polarity by draining it and then hooking it up backwards.
Agreed with Rdhog99. It is possible to charge a lead-acid battery backwards. Not that it works as well being reversed but it can be done.

My friend did it in his 60's era Corvette because he let it go completely flat after leaving a light on for a month. He then hooked up the clamps wrong when he used a battery charger.
Dave W. located in Gilbert, AZ
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed w/factory A/C
66 Corsa 140 4-speed
65 Corsa 140 4-speed
66 Corsa 455 Toro V8
65 Monza 455 Toro V8
65 Monza 4DR 140 PG w/factory A/C
65 Monza 4DR EJ20T w/5-speed

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bbodie52
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Re: Replacing reversed polarity battery

Unread post by bbodie52 » Wed Oct 18, 2017 6:48 am

:goodpost: :whoa: You are right. I had never heard of it happening and didn't think it was possible. After reading your comment, I did some research, and...
Battery Myth | Can a Battery ‘Reverse’ its Polarity?

Image

If you have a wet cell battery are filling it for the first time, and are using an old style, non smart charger, and short the terminals while you are filling it, yes it is possible to hook up the charger backward and reverse charge it. You would not necessarily notice a spark because the battery gains voltage as the battery is being filled, and if it is being charged while you are filling it, the short would not be a strong enough discharge to create a spark. If that was to happen, and a charger was hooked on backwards, or if it was installed in a kick start vehicle and hooked up backwards, then you can end up with a battery that has been charged, but backwards. Notice there are a lot of ‘ands’ in the above scenario. This situation is possible, but not very likely.

The second possibility is reversing polarity after the activation process. This is also rare, as it requires a sequence of errors to be present after the installation of the battery. The only way for this to happen would be to completely discharge the battery, either by leaving the key on, or by an unnoticed dead short that completely dissipated the charge over a few days. After that happened it would appear to be a dead battery.

Remember, a completely discharged battery is nothing more than an empty vessel. In order to gain a negative charge, it would then necessitate being hooked up backwards, and charged that way. So the real question here is: how can a battery reverse polarity after it has been installed? That same previously discharged battery would then be vulnerable to reverse charging, either by connecting the battery charger backwards, or by a charging system that reversed polarity (very rare, but still possible).

So let me restate: The only way for a battery that has a positive charge, to reverse itself, is for the battery to be completely discharged, and then reversed charged. We have seen this happen a couple of times, and it would be considered the more common of these rare situations.

For all intents and purposes, the battery will be ruined. You could technically charge it up, negatively, and continue to use it, but your plates are designed with the positive plates being lead dioxide, and the negative being composed of a sponge lead, which would now be reversed. Because the reversed battery is no longer formatted correctly, it will only work to a limited degree. The fact of the matter is, a lead acid battery cannot reverse its own polarity without an external stimulus. It is just not possible.
:link: https://www.batterystuff.com/blog/batte ... arity.html

You should check your battery with a multimeter to determine if your battery has been reversed or if the labeling on the battery terminals is correct.


If it turns out that your battery labeling is correct and that your Corvair is running a POSITIVE GROUND, you need to examine your alternator to find out if it was, in fact, designed for a positive ground system, as found in some older tractors. If that is the case on your Corvair, you would have to switch to a negative ground alternator in order to correct the battery on your Corvair, and switch your Corvair back to negative ground.

:confused: I'M SO CONFUSED!!!
Brad Bodie
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Image 1966 Corvair Corsa Convertible

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