Blast tube???  Do I need one of those too?  After my first taxi (with the cowl installed) I felt my alternators and was amazed at how hot they were.  I have decided it would be good for their lifespan to have a little cool air.  I didn't think to feel the coils.  I figure if they can survive under the hood of a Texas truck in rush-hour traffic in Austin, Texas in August, they should be OK for a/c use.  Besides, I have six of them.  If one of them fails, I still have five more to get me home.  I'm a little more paranoid about the alternators with an all-electric system.  Maybe I worry too much. 

Mark;

My alternator and coils are on the top of the engine.  They are in the exit air from the radiator, which generally stays below about 150F. I also have a louvered vent at the top of the cowl to help cooldown after shutdown; but it does get quite hot in there running static on the ground.  I have not had any coil failures, but have had a diode failure in the alternator voltage regulator.  I attribute that to the many hours of engine tuning standing still on the ground.  I have not added any cooling provision yet – thinking that with more flying and less ground running it may be able to survive. 

Alternator failure isn’t really an issue within the flyoff area because the batteries will always get me to the airport.  If you don’t have the update for the voltage variation in the EC2, the mixture will get too lean fairly rapidly as the voltage drops.

Al