Dunno bout this
I quite often fly from airfields with density alt of over 5000' in Australian bush and always approach at near full rich ready for go around and have never had a problem with cylinders or fouled plugs so I thought I should rethink this when reading this thread, this is what I came up with.............
*Always prime cold engine with 60lbs/hr fuel flow for one sec prior to start it will always start burnin & churnin within two revolutions
*Do same at 30lbs/hr with hot engine
*I quite often have to lean on climb above 5 or 6000' to keep the engine "tone" sounding correct
*I "gain control of the MP" and begin to enrichen prior to decent, I enrichen by 50'F before decent and keep it there until the circuit where on final I run nearly full rich depending on circuit density alt, this does not give thermal shock when done slowly
*If go around procedure is UP, UP & UP then I do not want to go from lean & hot upper cylinders to cold (thermal shock) just when I need full power. Saw a P68B damage a Lycoming 360 this way
*Have never had a problem with fouled plugs !!!!!!!!
*If we look at fuel line diameters and flows etc. we see that fuel velocity is around 520 mm/sec all things considered you are not going to heat the fuel appreciably with engine in the cruise getting fuel from a tank that is marginally above ambient because of return fuel
*vapour problems are either caused by low fuel flows & hot engine on the ground or cavitation or extreme temps where the fuel pressure is exceeded by vapour pressure
Hmmmm I am still rethinking my logic here whadya think
regards.............. Wayne
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