Narrative:

During preflight I noted that the oil was low in both engines. Being piston engines; I added one quart to the left engine and 3 quarts to the right. I notified maintenance; but as I had not flown this airplane recently and we did not see signs of leaking; we determined that it was just low and added the oil. I taxied and performed an engine run up. All systems checked good. After loading the aircraft I departed and; after clearing the terrain; proceeded on course. 10 minutes into the flight I was still climbing up to my cruising altitude of 11;500 ft and the right manifold pressure was decreasing. I increased the throttle control and as I was leveling off pulled both levers back to 26' of manifold pressure. At this point the left throttle was pulled back for cruise; the position was back considerably on the throttle quadrant (where it should be under normal circumstances) and read 26'. The right throttle was now full forward and only reading 21'. I had been monitoring the engine gauges also for engine temperature/mixture control and the right cht was at max and within seconds the oil pressure went from normal conditions at 75 psi; down to 20 psi (redline). Right then I decided to shut down the engine and return to [departure airport]. I was only 15 minutes out and decided that was my best course of action. I performed the right engine shut down and completed all checklists. I notified ATC that I was [returning]. They promptly cleared me back and handed me over to approach. I [advised of my situation] with approach. They gave me directions for a straight in. With the engine still secured I landed and exited the runway. The fire department met me; along with airport security; and our maintenance team.

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Original NASA ASRS Text

Title: PA-31-350 pilot reported an inflight engine shut down due to high cylinder head temperature and low oil pressure.

Narrative: During preflight I noted that the oil was low in both engines. Being piston engines; I added one quart to the left engine and 3 quarts to the right. I notified Maintenance; but as I had not flown this airplane recently and we did not see signs of leaking; we determined that it was just low and added the oil. I taxied and performed an engine run up. All systems checked good. After loading the aircraft I departed and; after clearing the terrain; proceeded on course. 10 minutes into the flight I was still climbing up to my cruising altitude of 11;500 ft and the right manifold pressure was decreasing. I increased the throttle control and as I was leveling off pulled both levers back to 26' of manifold pressure. At this point the left throttle was pulled back for cruise; the position was back considerably on the throttle quadrant (where it should be under normal circumstances) and read 26'. The right throttle was now full forward and only reading 21'. I had been monitoring the engine gauges also for engine temperature/mixture control and the right CHT was at max and within seconds the oil pressure went from normal conditions at 75 PSI; down to 20 PSI (redline). Right then I decided to shut down the engine and return to [departure airport]. I was only 15 minutes out and decided that was my best course of action. I performed the right engine shut down and completed all checklists. I notified ATC that I was [returning]. They promptly cleared me back and handed me over to Approach. I [advised of my situation] with Approach. They gave me directions for a straight in. With the engine still secured I landed and exited the runway. The fire department met me; along with airport security; and our maintenance team.

Data retrieved from NASA's ASRS site 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.