I have a 95 F350 with a 460 engine being used as a snow plow truck. Sometimes when I'm plowing snow, the alternator will stop charging. It only occurs when the snow billows up inside the engine compartment while I'm plowing. It's not a short or faulty ground as all electrical functions still work, it's just not charging. After awhile it'll "dry out" or reset and start charging again. It's never happened during dry weather or normal driving. I've replaced the alternator and main relay. This has been going on for months and so far no major failure has occurred. Is there a circuit breaker somewhere that trips or another relay in the charging circuit I can check? Any ideas or suggestions would be appreciated.

 

I had this problem with my plow truck, and it turned out to be the belt was slipping when it got wet with the snow blowing in.