Technical Battery Corrosion

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Technical Battery Corrosion

Michaelsfiat

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I have a 2013 Fiat 500 Sport and negative battery terminal is perpetually corroded
I just cleaned it the best that I could with out taking off (it was worse then that!)
I want to take it off but I want to make sure there are no complications other then resetting the clock?
Maybe I'll replace it with a new terminal but it's looks like its a Fiat part
Can I replace it with a terminal from a local parts store and I could rearrange the wires to make it work
Thanks
 

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Anyone have any suggestions about replacing the terminal or disconnecting battery any complications
 
Anyone have any suggestions about replacing the terminal or disconnecting battery any complications
Pouring boiling water over clamp works pretty well at cleaning up sometimes.
Spray with grease after cleaning to prevent further corrosion.

Do not have key anywhere near the car when disconnecting and do not dis connect into 10mins after removing key
 
Hi,

Should be no problem disconnecting the battery but follow process

Safety: Always remove the negative cable first, then the positive cable. When you connect the battery, connect the positive end first. Here is the order: Remove black, remove red, attach red, attach black.



I was worried about this too but as I had Start/Stop battery I had damaged it jumping and charging incorrectly and ended up with flashing mileage and warning light faults on the cluster.


New battery fitted did not initially cure the cluster faults and looked like an expensive visit to the dealer for a proxy alignment so left disconnected for 24 hours and then re-fitted and thankfully everything settled back to normal.......


That corrosion does look bad on yours but I would suspect just surface and no doubt you are residing in a regular damp atmosphere. Replacing those wire end fittings though requires special crimp tools and could be worse for you if not done properly.


Personally I would remove the connections and get some corrosion treatment. In the UK we have a product called Jenolite basically a mild phosphoric acid and it will stabilise the rusted area and treat the oxydisation. Just paint it on with a small brush and leave for an hour. We have a lot of classic cars with the old metal and brass Lucar connections and use this all the time as it cleans up all oxydised surfaces.


When refitting then liberally smear with dielectric grease..... again we do this on all our car earth points too. Some people use just a petroleum jelly like 'vaseline' but there are correct products designed to do the job.


Keep the surface of the connections always well coated and then you should get no further corrosion.


Farrah
 
Thanks for the replies
I am in Florida USA and it is a damp location
I looked up LiquiMoly and Jenolite but could not find it locally
But I have some dielectric grease I will use
Thanks again
 
The corrosion is caused by the acidic gas from the battery. Unseen, it is also landing on other stuff around, so the cause needs to be addressed as well as the effect.

Despite appearing to be 'sealed', the battery will have one or two breather holes, often well hidden, soometimes just a round hole at each end of the top, or maybe under the top overhang. This used to be a problem many years ago, but as battery technology has improved, cell gassing has reduced to almost nothing, which is why we rarely see corrosion nowadays.

Quickly recurring corrosion points to a battery that is gassing more than usual. The alternator could be overcharging, or the battery is dying, with at least one cell failing and causing the gassing. If it is the original battery, it is now 7 years old, so at the end of its life expectancy. Replacing it would be a good idea. If it is a recent replacement, check the alternator output, and if ok, have the battery checked by the seller or a decent garage.
 
A solution of Bicarbonate of soda(used in cooking and cleaning+water) will neutralise the acid(When the bubbles stop it's done) then a wash with water and dry.
As above it may pay to replace the battery, bit Vaseline on the posts and all well, don't replace the terminals.
 
Thanks for the replies
I am in Florida USA and it is a damp location
I looked up LiquiMoly and Jenolite but could not find it locally
But I have some dielectric grease I will use
Thanks again

Hi, good info all round(y)

The Jenolite is for the rust and oxydisation metal cleaning and not for the preventative grease as afterwards. It is just a weak phosphoric acid that can be sold for the DiY. Many quality alloy wheel cleaners for removing the brake dust debris are also phosphoric acid based .....if you go into any of your car parts stores you should see some products similar that will do the job.....like we also have one call 'kure-rust'.

I have seen the bicarb soda trick too and that works but you do need to get the whole terminals cleaned as capilliary action draws the moisture into the joints. This oxydisation here causes resistance which causes more heat and nothing better too for corrosion than moisture and heat...........other than the wonderful salt we put on our roads in the UK.

As well as using dielectric grease or vaseline on a lot of our cars we have actually silver soldered the earth crimped terminals underneath the car (not battery) as over the years had many problems when the wire and terminal has actually corroded inside giving a high resistance again as moisture penetrates down the twisted wire into the inside of the crimped end.

Farrah
 
That much corrosion on the negative post could be caused by an under-charged battery, so first check that the battery is charging correctly. A battery that has been idle all night should read 12.6 volts static. If yours is closer to 12v then give it a charge for a few hours, let it have a rest and then measure the voltage again.

If the voltage stays at the charged up voltage, then check the alternator isn't on furlough. At a fast idle (15-1800rpm) the battery should report 14.3 volts. If it's less than this, or if the car's lights glow brighter when you increase the revs from idle to fast idle then the alternator is slacking and just buying a new battery, or terminal wouldn't solve the problem.

If the battery doesn't hold 12.6 volts overnight, then you should start saving up for a new battery... although I'd hang on to November/December if it's good enough for now.

To clean the terminal.. wear gloves and keep your face away from it, since it's acidic and getting a speck of acidic in your eyes is a unique experience you don't forget.. Ahhhh Ahhhh

Remove the majority of the acidic dust/crud using a baking soda, Coca-Cola, tea or even plain water solution and a small wire brush (or your room-mate's toothbrush).

Dry it all off with a paper towel.... then remove the terminal from the battery post.. being careful not to splash any residual liquid into your face. Clean the outside and particularly the inside of the terminal with emery paper (sand paper will do) or wire wool until it's shiny. Anything not metal will not transmit electricity so it should be as clean as you can get it.

The battery post can be cleaned the same way. Wire wool seems best to me.

Replace the terminal and clamp it up tight. If it's loose, you'll have resistance and then more corrosion. Then cover the whole terminal with a thin coat of battery grease, or Vaseline, or even regular wheel bearing grease. Fiat used to recommend Vaseline so the new stuff may or may not be an answer to a problem that doesn't exist.. but my old battery lasted fine with whatever grease was in the garage, so it's not desperately important.

Use "a thin coat" just to cover everything. You don't need half a tub, since it's not lubricating anything, just making the terminal air tight/waterproof since it only corrodes in the presence of moisture, regardless of what else is going on.

Inspect it every now and again (when you check the oil) and when needed give it a fresh dab of the goo.

If you do get tempted to remove the terminal and fit a new one, first get hold of a battery terminal rubber boot. These fit onto the cable and then fold over the terminal to keep dust and dirt from sticking to the greasy.. but at the moment, I'd say don't replace the terminal or the cable unless you really can't stand how the old one looks.


Ralf S.
 
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Hi,

Have to say I am not a fan of wire wool or using wire/brass bristle brushes around electrical items.

Years ago we used to do it and once had a bristle from the brush come out un-noticed and short across two lucar terminals. Not really any damage but would worry me on cars with modern electronics any fine metal contaminates.

Also on items that are cadmium/zinc plated wire brushes and emery paper just end up scratching some of the good stuff still left.

Each to ones own and for sure when dealing near any chemical or acid cleaners eye and glove protection is essential.

I have seen coca cola used though as stated on cleaning silver and coins from oxydisation but again expect to see ants and flies nesting if you get it down the side of the battery and not cleaned off as they love sugary drinks.!!!!!

Farrah
 
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