What was found
AFTER TAKE OFF, ENGINE BEGAN SURGING, AIRCRAFT WAS YAWING LT AND RT, TORQUE WAS FLUCTUATING +/- 30 PERCENT. THROTTLE CONFIRMED OPEN, ENGINE BEEPED TO MAXIMUM N2 AND NR WOULD NOT GO ABOVE 94 PERCENT, UPON LANDING THE MECHANIC REMOVED AND REPLACED THE GOVERNOR AND STARTER GENERATOR AND THE AIRCRAFT WAS RETURNED TO SERVICE.