Technician reported discovering a clamp bolt protruding from a Thrust Reverser Drain Hole during an ETOPS pre departure walk around. The engine was opened and numerous clamps and hardware were discovered unsecured; missing; which Technician corrected.

Narrative

Upon receipt of aircraft from ZZZ to ZZZ1 I was on ETOPS check walk around. On R/H Engine Lower Left Hand Thrust Reverser Cowl saw a clamp bolt hanging out of the drain hole for the panel. After opening both left and right engine cowls found a clamp in bottom or engine cowl as well. After checking log book history found there was work done in area a few months back by an outside vendor. Upon further inspection found area of lower fuel loop going into the fuel nozzles saw where clamps were replaced. Suspect old hardware was not cleared of area before closing up engine cowls. Also found two clamps unsecured on fwd side of engine firewall fwd of fuel nozzles. Secured all loose clamps and inspected entire fuel loop and fuel nozzles for security and missing parts. None were found so suspect FOD was missed on close up. Better quality control and inspection after maintenance to clear all FOD and check for loose assemblies or parts taken apart to facilitate maintenance. Inspectors should of cleared all fuel nozzle work as well.