I have a 655e NH backhoe and i noticed near the fan belt at the bottom of motor a blue spark every 30 seconds or so at idle...? only at idle... my mechanic thought the motor wasnt grounded, so we did that and still have this arcing out problem... any ideas?? we changed the alternator today too and that did nothing... please help
update:: when i take off the fan belt and run the machine , the arcing stops....??? why
Static build up on the belt??? Try soaking it or misting it with water and see if it still does it. I'm suspect the air is real dry and it's just static. This is how a Van de Graaff generator works. http://en.wikipedia.org/wiki/Van_de_Graaff_generator