Failed air filter support tube?
- Thread starter Papaw
- Start date
SuperCub MD
Registered User
Collins, Wisconsin
It usually happens because the air filter is contacting the cowl. The repeated pounding of the filter against the cowl in flight will break the support tube at it's weak point. Adjust the filter/cowl to eliminate the contact, and the problem goes away. Welding in flat steel triangles on each side of the support tube will help eliminate the Weak point.
Mark,
Thanks for the repair tip, we are about to weld the tube now. I will check the air filter clearance and look for evidence of rubbing when we reinstall, but I as I recall the filter had good clearance all the way around. A new K&N filter was installed at the annual less than 10 hours ago and the tube appeared to be sound then. But, then I didn't suspect a 5/8 inch .059 wall 1020 or 4130 tube with only 96 hours to crack. I do not like that dome filter retainer system anyway.
It is always something. We lost the filter dome while shooting landings to verify that we had finally corrected an unbelievably persistent and violent tail wheel shimmy.
Cheers!
Thanks for the repair tip, we are about to weld the tube now. I will check the air filter clearance and look for evidence of rubbing when we reinstall, but I as I recall the filter had good clearance all the way around. A new K&N filter was installed at the annual less than 10 hours ago and the tube appeared to be sound then. But, then I didn't suspect a 5/8 inch .059 wall 1020 or 4130 tube with only 96 hours to crack. I do not like that dome filter retainer system anyway.
It is always something. We lost the filter dome while shooting landings to verify that we had finally corrected an unbelievably persistent and violent tail wheel shimmy.
Cheers!
