As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMBOUT LT PROPELLER KEPT ON INCREASING TO 1700 RPM EVEN AFTER CLIMB POWER SET. ALL ENGINE PARAMETERS WERE NORMAL. DURING POST FLIGHT OBSERVED HOLES IN BOTH EXHAUST STACKS AND LT PROPELLER FAILED TO ROTATE. REPLACED LT ENGINE POWER SECTION, OPS CHECKS NORMAL.