Narrative:

After loading cargo I taxied to runway 21 for departure with a 10 knot direct crosswind from the left. All systems indicated normal during the preflight engine run-up. The VFR takeoff procedure and initial climb went without incident; gear and flaps up; 40 inches and 2235 RPM. At 1;000 AGL I reduced the power to the top of the green arcs (33.5 inches and 1900 RPM). After setting the mixtures for climb I noticed the left engine lost over 5 inches manifold pressure and indicated a little above 25 inches. Increasing the throttle had little to no effect; so I began to troubleshoot by increasing the mixture and checking fuel pumps on. As I was adjusting the mixture control; I noticed the left engine oil pressure indicated zero and the motor was running a little rougher than normal. Reducing the power on both engines to around 20 inches; I began troubleshooting oil problems and pulled out the emergency checklist for 'sudden engine roughness.' the left engine still did not respond to throttle increase and began running much rougher with noticeable vibrations. The oil pressure remained at zero and oil temperature was climbing to around 85-90 percent. At that point I decided to secure the engine and referred to the checklist: propeller feather; mixture cutoff; fuel selector and pumps off; alternator off. With the engine secured; I turned back to the departure airport less than 10 miles behind and maintained 7;000 MSL. Because the problem occurred at a relatively low altitude; I had not yet contacted ATC to pick up the IFR clearance and returned VFR with unlimited ceiling and visibility to the airport on one engine. The approach and landing were without further incident and I taxied back to parking and shut down the remaining engine.

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Original NASA ASRS Text

Title: C404 pilot experiences engine roughness and loss of oil pressure during initial climb. The engine is shut down and the flight returns to the departure airport.

Narrative: After loading cargo I taxied to Runway 21 for departure with a 10 knot direct crosswind from the left. All systems indicated normal during the preflight engine run-up. The VFR takeoff procedure and initial climb went without incident; gear and flaps up; 40 inches and 2235 RPM. At 1;000 AGL I reduced the power to the top of the green arcs (33.5 inches and 1900 RPM). After setting the mixtures for climb I noticed the left engine lost over 5 inches manifold pressure and indicated a little above 25 inches. Increasing the throttle had little to no effect; so I began to troubleshoot by increasing the mixture and checking fuel pumps on. As I was adjusting the mixture control; I noticed the left engine oil pressure indicated zero and the motor was running a little rougher than normal. Reducing the power on both engines to around 20 inches; I began troubleshooting oil problems and pulled out the emergency checklist for 'Sudden Engine Roughness.' The left engine still did not respond to throttle increase and began running much rougher with noticeable vibrations. The oil pressure remained at zero and oil temperature was climbing to around 85-90 percent. At that point I decided to secure the engine and referred to the checklist: propeller feather; mixture cutoff; fuel selector and pumps off; alternator off. With the engine secured; I turned back to the departure airport less than 10 miles behind and maintained 7;000 MSL. Because the problem occurred at a relatively low altitude; I had not yet contacted ATC to pick up the IFR clearance and returned VFR with unlimited ceiling and visibility to the airport on one engine. The approach and landing were without further incident and I taxied back to parking and shut down the remaining engine.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.