"Full rich is horrendously rich"

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An airplane that hasn't flown in 8 years quits when going to full power. A turbocharged Mooney meters out less fuel as it climbs. Mike, Paul, and Colleen tackle these questions and many more in this episode. Email [e-mail] for a chance to get on the show.

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Eric is having trouble with his Aero Commander. The engine has only 150 hours but sat for 8 years. After an extensive annual, they test flew it. One of the engines dies at full power, but runs fine at partial power. The flow dividers were checked, the fuel lines were blown out, and the fuel servos were bench tested. Colleen suggests that it could be a blockage of the exhaust, especially given the long sitting time. Paul thinks it’s possible that a lack of air supply could be a problem. They suggest opening the alternate air to see if that fixes it. Paul said he would go through the entire induction system to verify it’s clear and open.

Will is struggling to get the fuel system set up in his turbo Mooney. As he climbs he says the fuel pump is decreasing fuel pressure. The manifold pressure starts to decrease when fuel pressure gets low in the upper teens. Mike said there’s nothing wrong with the manifold pressure or upper deck pressure. The line from the upper deck pressure to the fuel pump aneroid is bad. The aneroid thinks it’s seeing lower pressure as he climbs, even though it shouldn’t. He thinks there’s a leak in that line, the aneroid, or the upper deck pressure. He suggests pulling the b-nuts and replacing the seals first.

Jim is wondering about how to lean when flying low in a formation fly-over. With 10 airplanes and lots of throttle changes back and forth, it’s hard to know how to lean. Colleen suggests doing some tests at the same altitudes not in formation to see what sort of power settings he’s at and apply it based on those tests. Mike said he would lean to around best power.

Jason is a partner in a 182 and a potential new partner went for a test flight and found a potential issue. The rpm dropped 150 to 170 during the mag check, and he refused to fly the airplane. So he’s wondering if the pilot was overreacting or if he was right not to fly it. Paul said EGT rise is a better indicator than rpm drop. Very little drop or no drop could mean the P leads weren’t connected. Mike said bigger drops, like 300 rpm, should prompt a timing check. Switching to one plug has the effect of artificially retarding the mag timing. If it’s already retarded, that can make a large drop