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Finally got a stubborn Cessna 172 flap actuator to move after three days of fighting it.

The plane came in from a small field in Flagstaff with a complaint of asymmetric flap extension. I tried the book procedure, then heat, then penetrating oil, nothing. On a hunch, I disconnected the pushrod and rigged a small hydraulic hand pump directly to the actuator port with a pressure gauge. At about 350 psi it finally broke free with a loud pop. Learned that sometimes the book troubleshooting tree doesn't account for a completely seized internal bearing. Anyone dealt with a similar bind on a Piper Cherokee flap system?
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lauradavis
lauradavis1mo ago
Nice trick with the hand pump. Seen that on a Cherokee where the chain bound up in the housing.
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luna_craig58
Remember that Cherokee, @lauradavis? Was it the chain itself that got stuck, or did the guide just warp and pinch everything? I've seen both happen, and the fix is totally different. A bound chain is a nightmare if you don't catch it fast.
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ivan_craig
ivan_craig1mo ago
Which year was the Cherokee?
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