Tokirbymd
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- Joined
- Oct 17, 2019
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Tokirbymd
PA32 with PET1. At annual in May fixed an incorrect routing of the trim cable around the servo and worked perfectly all summer. Over last month has cooled some and now there is a stiff area mid-trim where the electric trim has a hard time overcoming resistance and slips. Hand trimming works but is palpably stiffer through this mid portion- more nose up and nose down regimes are ok. Also, for some reason tends to be stiffer when going in nose up direction and less stiff going nose down- actually electric trim works reasonably ok going nose down. This nose up area is the exact area that I use trim as I'm on short final so kind of a PITA. What I've tried- removed tail cone, cleaned and re-lubed jack screw. Cleaned all trim cable going in/out of rear trim drum. Cleaned cable going in/out of trim servo. Cleaned trim cable going in/out of front trim wheel. Pulleys I can access at the rear and just behind the access door seem free and aren't binding. Haven't opened the floor panel yet to check those pulleys out. However, the fact that it is only binding in the mid portion of trim travel and not and more fore/aft extremes suggests the problem isn't with a pulley. Also, that is is worse in one direction is odd. I've heard of some trim jack screw and barrel combos that can get out of size but would think that would bind more at one extreme rather than in the middle when the pressure is equal on both top and bottom of the drum. Any pointers as to where to turn next? My only other thought is opening up the whole bottom floor and checking/lubing every pulley. Last resort would be replacing cable and trim drum/jackscrew but not sure I want to go that far. Oh, and I videoed the trim servo during manual and electric movement- the spindle spins independently and appropriately with manual and then with electric the solenoid engages the bottom plate correctly. When it is binding the cable is slipping on the electric spindle but looks like its only because the tension/resistance is too high.
