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So I have read about the idle mixture ... just before pulling into Idle cutoff, that there should be a slight increase in RPM, showing that a slightly rich mixture is present when running on the idle circuit. I moved from an airport that was at 296 ft elevation to one that is 4530 ft last year... and so have been fine tuning my flying skills for DA and related changes needed at this new elevation.
When pulling the mixture, I normally have the engine running at about 1200 to 1500 rpm, slowly pull the mixture to to get some heat on the plugs to clean them off before shutdown. also taxe in a leaned position, do a mag check to be sure both are still working... as the mixture is pulled into idle cutoff, there is no RPM change.... so Monday night I tried it at idle speed, about 600 rpm, and again no rpm change going to idle cutoff....
So what is the recommendation??.. Idle too rich being that at 296 ft there was a slight rpm change last year, and now nothing, due to the higher altitude now??... woudl turning in the idle mixture screw 1/4 turn be the right direction to start??... Yes, I know, ask my A&P... need to find a new one, he is no longer answering phone calls...
I would think that the idle circuit is out of play when running at higher rpm settings, and that the mixture control is controlling the fuel going into the carb... thus the idle screw is not affecting anything.
Engine is O-360-A4A.....
When pulling the mixture, I normally have the engine running at about 1200 to 1500 rpm, slowly pull the mixture to to get some heat on the plugs to clean them off before shutdown. also taxe in a leaned position, do a mag check to be sure both are still working... as the mixture is pulled into idle cutoff, there is no RPM change.... so Monday night I tried it at idle speed, about 600 rpm, and again no rpm change going to idle cutoff....
So what is the recommendation??.. Idle too rich being that at 296 ft there was a slight rpm change last year, and now nothing, due to the higher altitude now??... woudl turning in the idle mixture screw 1/4 turn be the right direction to start??... Yes, I know, ask my A&P... need to find a new one, he is no longer answering phone calls...
I would think that the idle circuit is out of play when running at higher rpm settings, and that the mixture control is controlling the fuel going into the carb... thus the idle screw is not affecting anything.
Engine is O-360-A4A.....
