Blueish powder on postive terminal

IAmATeaf

IAmATeaf

IAmATeaf

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Wifes Civic wouldn't start this morning, she'd not used the car for a few days, got it jump started but there was all this light blueish powder on the positive terminla. Did a quick google which says it's bad so cleaned off as much as I could but is this an indication that the battery is on the way out?

Also it was low on water so topped up each chamber, could it being low on water have resulted in the powder?
 
The fumes that can vent from lead acid batteries during charging cause the corrosion. This is much less of a problem that it used to be as modern batteries are designed not to vent unless the pressure builds up too much. The fact that you have corrosion could point to a charging problem or possibly a leaking safety vent on your battery. The blue coloured corrosion comes from copper, usually the terminal clamp itself.

Remove the terminal clamp from the battery, clean up the battery post and terminal with a wire brush or the proper tool and apply a liberal coating a vaseline to both before reassembling.
 
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OK, wifes gone out for her shopping session that can't be delayed but when she gets back I'll wip the battery out, give a clean, top up the chambers as I ran out of de-ionised water and see what happens.
 
What is the battery volts, after it has been stud for 1 hour or more?

12.05v or less = replace.

If in doubt replace it, why faff around cleaning it etc, you have probably damaged it by not keeping it topped up.
 
You can remove all that blue powder by pouring boiling water over it, then clean and regrease the terminals. Make sure you know your radio code before disconnecting the battery.
 
If i ever have that i just boil the kettle then pour the water on the the terminal to wash it off.

Job done.
 
This has been educational for me.
I always wondered why a lead battery post gets that corrosion stuff on it. Never thought it was from the copper terminal... That also explains why giving the battery post (but not the terminal) a good greasing up never seemed to help much.
 
This is the reason cars changed from Positive earth to negative earth, on positive all of the cars earth connections went like this.
The correct name for it is "Verdigris"
I've also heard pouring coke on it works too, but I always use a wire brush.
 
The coke thing is a myth, in fact mythbusters tested it. Almost any water based solution will wash it away, a kettle of very hot water is quite effective.

Verdigris is a green pigment, copper chloride. I suspect the blue corrosion on battery terminals is more likely copper sulphate, given that batteries contain sulphuric acid. Then again I'm no chemist.
 
Boiling water poured, terminals greased and water all topped up. Am hoping that it's not too late and that the battery makes it else I'll need to replace the damn thing.
 
BullBoyShoes said:
you say you jumped the battery, would this marking then not be caused by arcing when you connected the positive terminal
Click to expand...

Not too sure what you mean.

Anyway /last salute/ the battery is dead, leave it overnight and it doesn't have enough to start the car the next morning so I've gone out and got an Exide 057 replacement for £55 from a friend of mine who runs a car spare parts shop. All fitted, car now starts and the wife's also stopped nagging me, for now :D

Thought I'd also check my car battery and that was also low on fluids so everybody out there check your battery. :D
 
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