Source: 2023Q3 Beartracks, Jared Yates
As we know, the Bearhawks (especially the 4-Place and Five) are heavy on the tail when parked. The main wheels sit somewhat forward, so it is very difficult to nose over with a Bearhawk, but the heavy tail is a tradeoff. One Bearhawker years ago told me that he would clean, inspect, and lube his tailwheel assembly every 50 hours. This may be appropriate depending on how the airplane is operated. I try to stick to a schedule of every year or 50 hours depending on which comes first.
Two days before we were to leave for Oshkosh, (isn’t it always?) I noticed that our tailwheel was not locking and unlocking very freely. It turns out that an insect had made a nest inside the tube where the locking pin resides. There was just enough room in the area occupied by the spring, but once we started steering, the nest was broken up and the dirt dispersed in that tube. It didn’t take long for the loose dirt to jam the pin in the locked position. This isn’t a big problem to fix, but it required removing the hex-head screw that connects the locking pin to the bushing that rides on the unlocking cam. When I went to remove it, that little screw snapped off. You can see the results in the lower part of the picture below.

This was not optimal. I knew that Eric Newton at Bearhawk Tailwheels would be happy to sell me a replacement locking pin and screw, but that would take a few days. I used to keep a spare of each, but hadn’t thought to resupply those spares since the fire. If we were going to fly to Oshkosh, I’d have to make new ones. I started with a long grade 5 zinc plated bolt from the hardware store, which had a nice unthreaded shank section. The first step was to drill a new hole to receive the screw. With a milling machine this would be an easy step, but with hand alignment it took two tries to get an acceptably-located hole. The hole needs to be centered, and I found that grinding a tiny flat spot gave the center punch, and subsequent drill bit, a little landing pad. Not having anything like the original screw, I used an AN-3 bolt, so I tapped the hole for fine threads. Once the hole was threaded, I cut the new pin to length and deburred the edges. The next problem was the bushing. I found that a stack of three AN washers looked just about right, and worked great. I added just a little thread locker to the AN bolt, and worked some grease in to keep the pin moving freely. Once it was all back together, I packed the locking pin tubing with grease so that the next insect wouldn’t find it to be an attractive housing vacancy. While it was an inconvenience to have to make the new parts on short notice, I’m thankful that we found the problem at home and not while trying to maneuver in the campground or at a fuel stop while on the trip.