What was found
ON 2/05/2013 PILOT REPORTED THAT PROP RPM EXCEEDED 1900 RPM, MAINTENANCE PERFORMED GROUND RUN AND COULD NOT DUPLICATE PROBLEM. THE AIRCRAFT WAS FLOWN BY OTHER PILOTS WITHOUT ANY PROP OVERSPEED ISSUE. ON 2/15/2013 PILOT REPORTED AGAIN THAT HE HAD A PROP OVERSPEED CONDITION, MAINTENANCE PERFORMED GROUND RUN OPS CHECK AGAIN AND COULD NOT DUPLICATE PROBLEM. RETURNED AIRCRAFT TO SERVICE. ON 2/16/2013 PILOT REPORTED OVERSPEED CONDITION AGAIN THIS TIME MAINTENANCE ADJUSTED MAX STOP ON OVERSPEED GOVERNOR AND RETURNED TO SERVICE. ON 2/20/2013 ANOTHER PILOT SAW THE OVERSPEED CONDITION, THIS TIME MAINTENANCE REPLACED THE PROP INDICATOR WITH A OVERHAULED UNIT AND RETURNED TO SERVICE, THIS FIXED THE PROBLEM.