Morris Minor Owners Club

Found an accumulation of salts (?) between the positive terminal and battery retaining clamp see pic. I’ve cleaned this up but wonder what’s causing it, no leakage from terminal or cells can be seen? Thanks John

PS it’s negative earthed

Missed pic off

The slightest vapours/spill can cause/start the corrosion.
Pour boiling water over the corrosion and it usually gets rid of it.
Wipe Vaseline over the corrosion area once cleaned and dry and that should keep the corrosion at bay.

Bearing in mind you have said it's -ve Earth, I assume the clamp is very close to the Terminals, perhaps only a few millimetres away.

I would suspect that general damp and minerals in the air, added to by the fumes from the venting of the battery (even 'sealed' batteries should have a small vent to stop case explosions) has resulted in the shortest possible path from Positive to Negative resulting in build up of sulphates.

I would clean it all up and increase the gap around the battery post, by grinding a curve into the retaining bracket, painting it, or even just putting a strip of insulation tape along it.


Remember that those 'Salts' are going to be acidic, so don't get any contamination on your clothes, especially if washing off as Phil indicated.

Note that it's also possible for batteries to have some fumes escape from around the posts, because of the different expansion rates of Lead and Plastic. It depends on if there is some sort of seal, or gasket around the post to prevent it

Many thanks for replies, the clamp was indeed close to the terminal so have radiused that as suggested, cleaned up and applied Vaseline so hope that works regards John