Running Hot

Today was a hot, but not blistering hot day in St. Louis (about 88 degrees & humid). I tried out some of the lean on climb input, and here’s what I came up with.

When I leaned (2000’ agl, 2500 RPM, 50 lean of peak which was 1390 CHT) the oil temp and CHT stopped climbing, but didn’t go down - stayed at 210 and 430 respectively, climbing to 8000’. Still seems troublingly high.

I also noted, in cruise, the differences by cylinder. CHT’s were: 360, 350, 330, 320, 350, 340. EGT’s were 1410, 1390, 1350, 1390, 1380, and 1420. These seem like pretty wide ranges - is this normal, and could it be related to my high temps? And are my temps high? Is GAMI the answer?



Seems to me if you are leaning in the climb you are compensating with the compensator. The engine is supposed to automatically lean for the best climb mixture. I am wrong in thinking this. My engine runs the coolest at full rich. I only lean at cruise to save a little $. I have a 20, missed your model.

I was wondering how you made out after our discussion this morning and am SHOCKED your values didn’t tumble. Additionally, even on the worse days…I have never been above 210 and 400 BEFORE leaning at 95 OAT.
I am thinking you have a cooling problem…but have no idea what it could be.
Sorry it didn’t help and good luck

although the redline is at 450°, you need to avoid operation at CHTs above 400° even on those normally-aspirarted Continentals. They don’t like it and 450° is really the limit. Make sure you leave the fuel pump on throughout the climb. Try this: Climb with full power, full rich, fuel pump on and 115 KIAS (SR20). Check that you have a fuel flow of 18 gals initially. Even on hot days, this keeps my CHTs in the mid-green range. Above 5000’ I start leaning a bit for climb but not much.
The differences in temperatures is a problem we all have. These engines just won’t do better…

Phil N199CD

many of the earlier 20’s have high ‘caution zone’ high oil and CHT temps on climb-out on hot days and try to bring those levels down by leaning on climb.
I don’t believe later models have the same issue. If you are ‘cool’…keep it full rich.

Yep, I have a later model 20 #1192. Sorry to but in.

no apology necassary…I just didn’t want you even thinking of leaning esp. on climb out if your temps aren’t seeing ‘red’