Lessons learned: 1. Keep good flight data and refer to if often, the only way to catch gradual trends. 2. A cooling system in an aircraft definitely needs some sort of screen or filter. I may try one of these http://www.babymall.com.au/tefba/ 3. 230 F does not seem to have hurt my 13B, I have probably 10 total hours flying at that temp. Keep the shiny side up! Chuck Dunlap N616RV 13B