If the battery case itself is dirty, leakage current can cause corrosion. I
use those silly little felt things you can buy for a buck. You need to
clean both posts and cable ends very well and be sure to brighten the
contact surface of each before reassembling. If it is an aftermarket or
replacement clamp, think about replacing the whole lead.
I used to do a good cleanup, then smother the battery post and clamp in
Vaseline after it was reassembled. It worked very well, especially after
everything warmed up and the Vaseline ran down in the gaps. Kinda messy,
Sometimes corroding clamps can be a sign of other problems. If the battery
is old and failing, it may be gassing too much and leaving stuff on top. A
goofy charging circuit can cause this, too. In really bas cases the battery
actually boils over... very messy and dangerous.
What car do you have and how old is the battery, maybe someone here can be
more helpful with the specifics.
Hope this helps! PoD
Another problem is the case cracks at the post allowing fumes from the cell
to come up around the base of the post. Happens when you try to tighten the
clamp without holding it. You can remove the cable and seal it with the
stuff they sell to repair cracks in the case.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.