Hi all,
I have been experiencing some mixture issues in flight and I could use some help thinking about the problem. I believe the issue has been present for the last ~100 flight hours, but yesterday developed from curiosity to concern.
After leveling off at 2000' (for a short local brunch run), I leaned my IO-375. My typical procedure is to pull power to 62%, then lean for 60%, which gives me LOP burn of ~7.8 gph. After a few minutes I heard the RPMs drop and found that my fuel burn had dropped to 7gph and power was low. I enriched the mixture and continued the flight. A few minutes later I looked down and found that my burn was up over 10gph. Again I adjusted and continued the flight.
On the way home I experienced the same issues, but with wider and more frequent swings in consumption and power. I bee-lined for home and pushed mixture to full rich, thinking that the last thing I wanted was for my engine to lean out in flight. Full rich was burning >20gph! For reference, I burn ~15gph on take off. I started to worry that I was going to fowl the plugs, but by this point I had the runway made, so I left mixture at full rich and landed.
What could be going on here?? Maybe the mixture cable is slipping in its housing? Possibly an issue with the fuel injection?
Thanks,
Dan
I have been experiencing some mixture issues in flight and I could use some help thinking about the problem. I believe the issue has been present for the last ~100 flight hours, but yesterday developed from curiosity to concern.
After leveling off at 2000' (for a short local brunch run), I leaned my IO-375. My typical procedure is to pull power to 62%, then lean for 60%, which gives me LOP burn of ~7.8 gph. After a few minutes I heard the RPMs drop and found that my fuel burn had dropped to 7gph and power was low. I enriched the mixture and continued the flight. A few minutes later I looked down and found that my burn was up over 10gph. Again I adjusted and continued the flight.
On the way home I experienced the same issues, but with wider and more frequent swings in consumption and power. I bee-lined for home and pushed mixture to full rich, thinking that the last thing I wanted was for my engine to lean out in flight. Full rich was burning >20gph! For reference, I burn ~15gph on take off. I started to worry that I was going to fowl the plugs, but by this point I had the runway made, so I left mixture at full rich and landed.
What could be going on here?? Maybe the mixture cable is slipping in its housing? Possibly an issue with the fuel injection?
Thanks,
Dan