[vettestr]

Well the old formula is E= I/R .
A bad motor brush or bad ground would cause current to increase but 75 amps is about what a starter cranking can draw. Something not right here and a 18 gauge wire (on most fans) would be smokin!!
I bet ya it is more like about 17 to maybe 20 amps for 2 fans and we need to verify all readings and start over here.

Edited to go back and re-do math ...... return from lunch at ????