HI Bill,
The comments I made regarding engines in the ambulances was in reference to a previous question made regarding running an engine to rich or slow. I could believe the damage was caused by running to cool. I had a 94 Dodge with a Cummins diesel in it, when you idled, the engine temp would stay at the bottom of the guage. There was very little heat generated while it idled. It would even go from a running temp to a cold guage reading if you pulled in and let the engine idle for more than 20 minutes. That was with the entirely stock package under the hood. My point in reference was only that running under conditions that the engines werent exactly designed for can lead to other problems. Run them the way they were intended and under appropriate loads and conditions and you will have a long lived engine. Happy flying, Jeff