What was found
J/S REPORTED AN OILY ODOR IN COURIER COMP. WITH VISIBLE OILY SMOKE. THE FIRST OFFICER STATED THAT JUMPSEATERS NOTIFIED THE CREW THAT OILY SMOKE WAS COMING UP THROUGH THE FLOOR VENTS. F/O VERIFIED THAT IT WAS NOT CONDENSATION & WAS OILY SMOKE. NO SMOKE OR ODOR WAS DETECTED IN THE COCKPIT. COMPLAINT HAPPENED JUST AFTER THE F/O CRANKED THE TEMPERATURE UP IN THE COURIER COMPARTMENT. WHEN THE F/O CRANKED IT BACK TO COOL, T/S PER TSM 21-20-00 FIG 210. PERFORMED NUMEROUS DUCT BURNOUT WITH APU & ENGINES WITH BOTH PACKS. THE LAST BURN OUT, HAD NO ODOR. A/C JUST CAME OUT OF C-CHECK. SUSPECT HYD CONTAMINATION DURING CHECK. THERE IS NO CURRENT HYD LEAKS. THERE WAS CONTAMINATION IN THE PNEUMATIC DUCTS VIUALLY.