[June 11, 2013]

I finished up the oil change today. One item I didn't check on my last annual was the oil screen. The reason I skipped it was I only had about 15 hours on my oil, and didn't feel like wasting money on new oil just to check the screen. Another reason for removing the oil screen bolt was there was a slight drip in this location. I am pretty sure it was from me re-using a crush washer when I checked it last time.

The proper crush washer to use here is an AN900-16. There is no torque spec, but it is supposed to be tightened 135 degrees after contact. Also, this is a split crush washer. The split side of it is supposed to face the engine. I did all of this and safety wired it. Hopefully my drip is fixed!

My CFI the other day noticed my engine sounded rough at idle, like it was running rich. At 1000 RPM is leaned it back and saw there was a 260 RPM gain before the engine wanted to die. He said this was too much RPM gain and it would lead to my plug fouling up.

I took some time today to adjust the idle mixture while the cowl was off. Here is the adjustment point. On my fuel servo, it indicated which direction to turn this adjustment for making the mixture more rich/lean.

So here is where I ended up at. This is running at full rich - 880 RPM.

And with the mixture pulled back to get peak RPM's - 940 RPM. Exactly 60 RPM difference. Once I made this adjustment to the idle mixture, I noticed my idle speed went up significantly. This makes sense since the engine is now running leaner. I needed to adjust the idle screw about 1/4 of a turn to get a lower idle in the 600 RPM range. The engine runs much smoother now.

I finished off the day with practicing some of the aerobatic maneuvers I was recently taught. I'll be the first to say I have a long way to go. I am over-turning coming out of my aileron rooms.My entry to loops/hammerheads aren't straight up (although I believe the Go-Pro in this camera mode exaggerates my launch angle). However, it is a blast to go up and do this, and I have something to work towards improving.



Last Modified: June 24, 2024