Checked Oil Temp Calibration
I finally got around to checking the calibration of my Rochester oil temp gauge/sender. I heated up some water in the microwave and dipped both the sender and my Fluke thermocouple in the hot water. The gauge read right on between 180F and 200F. I also used a 39 ohm resistor to simulate 245 degrees and that was right on as well. I'm calling it good.
Yesterday I made a flight to Elizabethton, TN [0A9] and the OAT on the ramp was 30C. The plane sat there for three hours in the hot sun and I had no problem with the engine dying on me as I taxied for takeoff. So I'm becoming more convinced that the carb was getting heat soaked by the oil sump and the additional air to my oil cooler has at least helped, if not fixed the problem. During my condition inspection next month, for good measure, I'm planning to add a 1/16" phenolic spacer and two gaskets between the sump and the carb.
Also, I bought a $16 digital temp gauge on Amazon and intend to install the probe in the carburetor so I will know for sure what's going on in there.