I have a nice 12 V. Battery charger that I use on my Vanagon. The little muffin fan died I replaced with a another 12V. ball bearing fan but the power supply to said fan is putting out 17 V. how long do think said fan will last under these conditions? Over the last 10 years i have become fond of this battery charger is it time to let go? The charger itself seems to be working fine.Thanks, Bill Witz 84 Westy Tiico