Engine Adjustments

It has been really helpful having my dad in town to help with these final preparations. Today we drilled holes in the outboard aft corner of each fuel bay hatch. These holes will allow the fuel to drain more readily if the tanks begin to vent like they did yesterday. I also added the labels to the top of the wing that show the fuel tank capacity. I did a final check of the fuel fittings to make sure that none had been leaking overnight, and we took a lunch break. After lunch we ran the engine for a while to make adjustments to the carburetor for idle mixture and idle RPM. The theory is that the mixture adjustment should be somewhere between 1.5 and 2 turns out from fully closed. I was aiming to set the idle at around 700 or so. We made those adjustments, and while the EAA videos talk about looking for a 50 RPM rise when the mixture is fully leaned to stop the engine, we were seeing around 30. I taxied out to the runup area to check the static RPM, which was 2600. This should be 2700, so I’ll start by adjusting the governor stop to see if that is the limiting factor. If it isn’t the governor, then it might be the low pitch stop.

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