Add washers to the bolt
Tightening the bolt where the F-1287E push-rod attaches to the horn may not be the fix for you .... because the nut is likely bottoming out on the shank of bolt. There was a thread about this here on VAF quite a while back.
The AN3-10A bolt used at that location is a tad too long. I ended up adding an AN960-10 washer under the head of the bolt and in addition to the AN960-10 washer that goes under the AN-365-1032 lock nut, I added an AN960-10L washer. In my case, doing the above allowed the shank of the bolt to pass through the horn and the additional washers prevented the nut from bottoming out on the AN3-10A bolt's threads and leaves about three threads showing beyond the lock nut. Also verify you have AN960-10 washers on both sides of the MM3 bearing ... (between the horn and the bearing).
Enjoy your 12
RV-12 Wings, Empennage, Fuselage, Finishing, Avionics and Powerplant kits all completed
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