Sabremech Posted January 27, 2017 Report Posted January 27, 2017 (edited) Peyton and I will reinstall the trim jack screw assembly in a week or so. We'll report back on it's operation after repair. David Edited February 14, 2017 by Sabremech 2 Quote
carusoam Posted January 27, 2017 Report Posted January 27, 2017 Wow! Really great photos. A set of Timken ball bearings in there. That photo really explains how the old and crusty grease tries to lock things in place. Best regards, -a- Quote
Brandontwalker Posted February 2, 2017 Report Posted February 2, 2017 On 1/26/2017 at 7:15 PM, Sabremech said: Peyton and I will reinstall the trim jack crew assembly in a week or so. We'll report back on it's operation after repair. David Any luck on the reassembly David? My electric trim would not work for me last night and I suspect it is the same issue. It works fine on the ground, but would not work in the air. If you have not reassembled yours yet, would you mind taking some photos to document the process so I can wrap my head around how big of a job it actually is? Brandon Quote
PeytonM Posted February 2, 2017 Author Report Posted February 2, 2017 We just got the jackscrew assembly back from a cleaning and relubing. We will put it back in the airplane early next week and we will take pics. Can u move the trim wheel manually? Try it from full nose up; that was the real test for me. I could not budge it. Quote
Brandontwalker Posted February 2, 2017 Report Posted February 2, 2017 2 hours ago, PeytonM said: We just got the jackscrew assembly back from a cleaning and relubing. We will put it back in the airplane early next week and we will take pics. Can u move the trim wheel manually? Try it from full nose up; that was the real test for me. I could not budge it. I can move mine manually, but I can tell it is stiffer than it once was. Quote
Sabremech Posted February 2, 2017 Report Posted February 2, 2017 After working on Peyton's airplane, I'm going to remove the jackscrew on mine and disassemble, clean, repair and reassemble it. Mine seems to work ok, but this appears to be a part that's way overlooked. David 2 Quote
MB65E Posted February 3, 2017 Report Posted February 3, 2017 Wow! Those poor bearings back there. Not much help lubing them over the years. I had no idea. Is there a hole to squirt something in the bearing cavity? I wish I had large tubs of CorrosionX, tri-flow, mouse milk, epoxy primer... -Matt Quote
cliffy Posted February 3, 2017 Report Posted February 3, 2017 Be careful of the thin shims inside the bearing block when you pull it apart Make sure they go back in the same way they came out. And, no there is no way to lube the bearings without tearing the unit down. As Sabermech says, it's way neglected by most everyone. I use a 2X4 to hold the tail hinge open when the jackscrew is removed. Just put the "4" side between the two bulkheads. Holds it fine 3 Quote
Amelia Posted February 5, 2017 Report Posted February 5, 2017 While you're in there mucking around, you might want to see if Mooney Service Instruction M20-88A applies, or has been accomplished. Quote
Sabremech Posted February 5, 2017 Report Posted February 5, 2017 Since the problem addressed in M20-88A is not what's happened to this aircraft, probably will bypass it for now and return this aircraft to service. David Quote
Sabremech Posted February 7, 2017 Report Posted February 7, 2017 Trim jackscrew has been reinstalled. Works like a champ in all phases of operation. Final rigging tomorrow and then return Peyton's airplane to service. David 1 Quote
DonMuncy Posted February 7, 2017 Report Posted February 7, 2017 I'm not sure I understood all of what took place. Was it just gunked up and needed cleaning? Was it just old dried up grease that caused the problem. Quote
Sabremech Posted February 7, 2017 Report Posted February 7, 2017 2 minutes ago, DonMuncy said: I'm not sure I understood all of what took place. Was it just gunked up and needed cleaning? Was it just old dried up grease that caused the problem. Yes, it was binding up from old hardened grease. Just disassembled and cleaned thoroughly, then reassembled. Quote
Hank Posted February 8, 2017 Report Posted February 8, 2017 ^^^^^ That's often the case. If yours is tight, that's the first place to check. Then refill it with fresh, new grease, and top it off every annual. Quote
DonMuncy Posted February 8, 2017 Report Posted February 8, 2017 4 minutes ago, Sabremech said: Yes, it was binding up from old hardened grease. Just disassembled and cleaned thoroughly, then reassembled. Wonderful. We all like a good ending. And no parts required. Quote
Sabremech Posted February 8, 2017 Report Posted February 8, 2017 1 hour ago, Hank said: ^^^^^ That's often the case. If yours is tight, that's the first place to check. Then refill it with fresh, new grease, and top it off every annual. If it's tight, remove it and disassemble it for a thorough cleaning. Adding more grease won't solve the issue completely and may come back to bite you when you really don't want it to. Quote
Yetti Posted February 8, 2017 Report Posted February 8, 2017 good to see things and how to fix things Quote
Sabremech Posted February 9, 2017 Report Posted February 9, 2017 All done and ready to fly. Rigging was quite easy as we took some measurements before disassembly and then used those to start with on reassembly. David 2 Quote
cliffy Posted February 9, 2017 Report Posted February 9, 2017 When you fly it try to get it to move to extreme ends of use by slowing down and speeding up. See if it loads up at different tail loads. Also give it enough time up high where it is cold to see if it tightens up with cold air. Did you use a low temp function grease? Mine changes torque needed at different CGs and speeds. Quote
Sabremech Posted February 9, 2017 Report Posted February 9, 2017 10 hours ago, cliffy said: When you fly it try to get it to move to extreme ends of use by slowing down and speeding up. See if it loads up at different tail loads. Also give it enough time up high where it is cold to see if it tightens up with cold air. Did you use a low temp function grease? Mine changes torque needed at different CGs and speeds. That will be up to Peyton if he wants to be a test pilot for a flight, but I suspect he won't as it's back to how it was when new. Grease used was what was called for in the maintenance manual. Quote
Jerry Pressley Posted February 10, 2017 Report Posted February 10, 2017 The problem we have found along this line lately is binding on the trim box. Electric trim forces the box into a bind when trimmed for landing. Amelia's was so tight it took a pair of vice grips to free ti. We have another 231 here now with a similar problem. When I landed it I used the elec trim to trim nose up and when taking off again it was near impossible to retrim. I wonder if it would be possible to adjust more nose up and less nose down into the system. I never had a problem with too much nose down trim. Of course if it were loaded nose heavy>>>>>>>>>>>>> Quote
PeytonM Posted February 13, 2017 Author Report Posted February 13, 2017 I finally flew today after AOG for 36 days, but who's counting? Two hours, four TOs and landings, manually trimming for the whole flight. The trim wheel moves easily & smoothly, with even less effort than on the ground. A special thank you to David Staffeldt and Jason Doscher. I could not have done this project without these two gents. I learned a lot. Maybe I'll celebrate with a flight to SnF!! 1 Quote
Mcstealth Posted February 13, 2017 Report Posted February 13, 2017 On January 26, 2017 at 7:15 PM, Sabremech said: Peyton and I will reinstall the trim jack crew assembly in a week or so. We'll report back on it's operation after repair. David Been a long week I take it. 1 Quote
ArtVandelay Posted February 14, 2017 Report Posted February 14, 2017 While you're in there mucking around, you might want to see if Mooney Service Instruction M20-88A applies, or has been accomplished. I had this problem today, I will look at doing SI88 at my next annual, ended up having to put wrenches on it to free it up. Quote
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