Thanks Naveen and Doc for your helpful suggestions wrt to the heat shield.
The problem will be attacked one step at a time.
As it is, the servo heat shield has a big negative pressure zone right behind it. If we subscribe to the laws of fluid dynamics (gasses are treated as fluids) then the open gap produced by the open cowl flaps will afford us a considerable flow of air out of the cowl. The low pressure zone behind the t.e. of the open cowl flaps will suck the air out of the hot chamber. This should surely help with the cooling of the servo/heat shield.
If one stands behind the running engine with cowl on, and allows the engine to warm up, and then places a hand behind the cowl flaps you can actually feel warm air emanating from the gap. It is never hot, but just warm. The laser temperature gauge that I use for CHT's will come in handy later to test the level of heat in that servo area.
Then if the temperature in the area in question is too high ( "too high" being defined as the temperature at which the servo no longer works as it should) then we will have to resort to a Doc or Naveen solution in addition.
Of course, we mustn't forget that the servo may not operate correctly because it is too near to EMF splattering around from the close engine and ignition unit.
Also, it must be remembered that the choke servo is designed to run only when the engine is cold. Think about it! When will we ever use the choke, baring start up, unless it is an emergency and we want to use the choke to stop the engine ?
Stay tuned.
Ken
__________________ To repair.
102" Meister P-47 Moki 150
1/4 Scale P-47 Moki 400
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Ziroli Hellcat Moki 150
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