DV8Pilot Posted March 8, 2021 Report Posted March 8, 2021 Hello to everyone, I’ve got a new to me 1971 Chaparral (M20E) and noticed that on takeoff, while accelerating through 35-40 mph IAS, the flaps drift up a few degrees. Confirmed it by setting takeoff flaps in the downwind, landing with that setting, and they drifted down the same amount as up. There’s very little slack in the flaps at either full up or full down, but a small amount in between. Flaps move in unison with each other. No issues extending them or retracting them. I can’t find any tolerance limits of play in the service manual. Has anyone else experienced this? Attached video shows the amount of play at indicated takeoff. Thanks, DV8 IMG_1881.MOV Quote
carusoam Posted March 9, 2021 Report Posted March 9, 2021 Welcome aboard DV8! There is plenty of things to check on... Most likely something has aged in the system... Speaking of systems... Did you mention if you have the electric or the hydraulic flaps? Type of system will be helpful for giving insight... Are you moving the flaps with just light hand pressure in the video? There isn’t any tolerance... because normally flaps don’t do that at all... for either the electric or the hydraulic system... PP thoughts only, not a mechanic... Best regards, -a- 1 Quote
Guest Posted March 9, 2021 Report Posted March 9, 2021 The fact that the flaps move in unison suggests an issue with the flap actuator. Remove the last belly panel to expose the actuator for inspection. Clarence Quote
DV8Pilot Posted March 9, 2021 Author Report Posted March 9, 2021 Thanks guys. electric flaps; movement is from slight hand pressure. I’ll take a look at the actuator Quote
Mooneymite Posted March 9, 2021 Report Posted March 9, 2021 (edited) On my 74 C, that symptom was caused by the deterioration/compression of the rubber spacer on the flap drive linkage. Simple fix. Edited March 9, 2021 by Mooneymite 3 Quote
DV8Pilot Posted March 9, 2021 Author Report Posted March 9, 2021 @Mooneymite Thanks! First item I'll inspect once I drop the belly pan. DV8 Quote
Mooneymite Posted March 9, 2021 Report Posted March 9, 2021 (edited) 7 hours ago, DV8Pilot said: @Mooneymite Thanks! First item I'll inspect once I drop the belly pan. While you are in there, you might as well grease the flap drive....this sometimes gets "overlooked" on annuals. Just unscrew this cap and fill it with the appropriate grease. I think it's Aeroshell #6, but not positive. Edited March 9, 2021 by Mooneymite 1 Quote
PT20J Posted March 9, 2021 Report Posted March 9, 2021 27 minutes ago, Mooneymite said: While you are in there, you might as well grease the flap drive....this sometimes gets "overlooked" on annuals. Just unscrew this cap and fill it with the appropriate grease. I think it's Aeroshell #6, but not positive. My M20J manual calls for lubing the ball screw every 100 hrs with Lubriplate 630-AA and the gearbox every 500 hrs with MIL-PRF-81322G (Aeroshell 22). Skip Quote
DV8Pilot Posted April 8, 2021 Author Report Posted April 8, 2021 Update: Using @Mooneymite’s suggestion we got into the belly pan and discovered the worn bushings. LASAR had them in stock; four required. Replaced them and returned to service. No idea how old the previous bushings were. The whole process took about 3 hrs from start to finish with most of the time being spent on removing and replacing the belly pan. 4 Quote
carusoam Posted April 8, 2021 Report Posted April 8, 2021 Great follow-up DV8! Best regards, -a- Quote
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