[avengingangel]

I have about 400 hrs on my 4. 100 of which i've put on. The problem is with the cowl hinging system. I seem to eventually start breaking the hinges. I asume this is from vibration. I think I have the aerobatic rubber engine mounts. I have a wooden ed sturba prop as well. Anyone else experience this and how did you rectify it? It doesn't seem as though there is any excess vibration from inside at least nothing different than any of my other airplanes.

 

[Dean Pichon]

You have lots of company...

There is much info in the archives on this. I had similar experiences with my -4 with about the same total time. I switched to Skybolt fasteners along the sharply curved section (upper cowl to firewall) and to extruded hinge stock for the upper-to-lower cowl joint. So far so good, but it's only been a year. It was a fairly big job - since it meant no flying for the month or so it took me to complete the task. I'm guessing it took about 40 hours. A week's work once you have the plan thought out and all the materials on hand. Plus extra time to repaint the cowl, of course.