What was found
COCKPIT ODOR OBSERVED IN COCKPIT DURING CLIMB AND DESCENT AND TAXI. ODOR NOT OBSERVED AT LEVEL CRUISE IN THE HIGHER FLIGHT LEVELS. ODOR WAS CERTAINLY COMING FROM COCKPIT VENT WHEN THEY WERE FULLY OPEN. ODOR COULD BE DESCRIBED AS A SKUNK. VERY STRONG. ALSO COULD BE AN OIL/GREASE ODOR. ODOR OCCURED WITH AND WITHOUT ENGINES OPERATING. ALL AIR COMING OUT OF COCKPIT VENTS HAD THIS POTENT ODOR THAT CAUSED BOTH OF US TO EXPERIENCE HEADACHES. MOST NOTICEABLE WHEN WE DESCENDED BELOW AROUND 20,000FT. OWNER DID NOT REPORT ANY ODOR FROM THE CABIN. SEEMS JUST ISOLATED TO THE COCKPIT AC VENTS. REMOVED AND REPLACED R/H FACE WEEMAC HOSE DUE TO IMPROPER ROUTING. IAW AMM 21-21-00. OPS CHECK GOOD.