What was found
(CAN) OVERHAULED COMPRESSOR ASSY WAS INSTALLED ON ENGINE AS PER ALLISON 250-C20B MM. SATISFACTORY GROUND RUN/LEAK CHECKS WERE CARRIED OUT. SATISFACTORY TEST FLIGHT AND POWER CHECKS WERE CARRIED OUT. THE HELICOPTER WAS PUSHED INTO THE HANGER AND LEFT FOR TWO DAYS, FOLLOWING WHICH THE HELICOPTER WAS PUSHED OUTSIDE AND A START ATTEMPTED. THE IGNITOR FUNCTIONED BUT THE ENGINE WOULD NOT CRANK. AFTER SOME TROUBLESHOOTING, IT WAS FOUND THAT THE COMPRESSOR WOULD NOT TURN. THE COMPRESSOR ASSY WAS REMOVED AND SENT BACK TO THE OVERHAUL SHOP FORINSPECTION.