battery cables shorting out, smoking
 

Hey guys, my wife's car is inop and need sine help. About a week ago, she gets home from with, and tells me that during the day, she would occasionally get a burning smell after she parked. I confirm this when she pulls the cart in the garage. Did some investigating, and found that the heater hose, and the oil cooler plastic90 degree fitting under the vacuum pump were melted. I put it off as old age, and ordered up the new parts, and parked the car.
A few days ago,I needed to move the car, but the battery was completely dead.put it on a charger over night, but it would not hold a charge.
Yesterday, I installed the new hoses, hooked up the new battery, and all seemed good. About 10 seconds later, smoke starts billowing from behind the vacuum pump.
The positive cable is charred, and possibly melted.
I believe the same battery cable is what melted the hoses.
Can this be just a simple battery cable replacement fix? But, why would the cables short out? How would the sheathing get damaged?
Any help would be appreciated..
Tia
05 c230 150k miles

Had a similar situation on another car long ago and far away
the positive cable is chafing against something till insulation wore through. Just have to follow it till you find the spot. Depending on how looks, you may be able to tape it up or replace it. Then add a cable clamp to keep it from chafing again.