What was found
HELICOPTER PILOT LANDED TO HOOK UP LONG LINE (UNDER FAA PART 133), HOOKED UP LONG LINE. PILOT HOVERED INTO POSITION FOR AN EXTERNAL LOAD LIFT AND HEARD A LOUD GRINDING NOISE AND HAD AN ENGINE CHIP LIGHT. HE LANDED THE ACFT, SHUT IT DOWN AND CHECKED THE CHIP PLUGS. METAL WAS FOUND ON THE TOP ENGINE CHIP PLUG. HE REINSTALLED THE CHIP PLUG AND FOUND THAT THE ENGINE HAD FROZEN UP AND WOULD NOT ROTATE. A RENTAL TURBINE WAS INSTALLED AND THE ACFT WAS RETURNED TO SERVICE.