Plans: 1. Test the oil cooler for leaks and overall cooling performance of the aircraft. Status: Complete: After running the engine again I feel the temperature concern has been resolved. I ran the engine and varied the throttle over about ten minutes. Running the engine at about 3500 RPM continuous would drive temps up to about 210 degrees on the water and 220 degrees on the engine oil. Both temps dropped back down to about 200 degrees after returning to idle. Had I been airborne I feel the additional airflow would have dropped the temperatures into a solid safe range. The rattle i heard has gone away as well. Securing the oil cooler hoses seems to have done the trick.
Now the bad: during the test the oil pressure suddenly dropped to zero. I shut the engine down and looked for evidence of leaks and found none. I did however observe that the oil pressure sensor showed evidence of high heat. The connector was slightly melted. This strongly suggests that at some point, probably before I added the thermal tape, some damage occurred. The wiring was wrapped with fire sleeve but apparently that was not good enough for the temperature involved. It is possible the problem might lie elsewhere but this looks like the place to start.
