Originally Posted by Dave H

I tried opening mine up to see if I could help. When I took the steering mechanism off I could see the spring inside behind the steering tension adjustment screw. Running in the same up-down direction it appeared. Not sure how it came out if you followed the directions, but hey stuff happens. I chickened out in going any further, wasn’t sure if I should start with the inner larger screws or the smaller outer ones. But I suspect the spring goes across 2 pins, one for each direction of wheel travel, assuming it’s like other radios I have dissected. Wiggle the wheel maybe you can see something.

If you can’t figure it out, perhaps send a PM to RCGaryK. He works for Horizon, maybe he could take some pictures to help you out. (You’re welcome Gary ) Good Luck.