• If you log in, the ads disappear in the forum and gallery. If you need help logging in or getting registered, send request to: webmaster@southernairboat.com

Lycoming valve issues

jtstric3

Active member
Trying to see if anyone might know what cause this valve to fail? It was a brand new valve(yes brand new not used). I have a 0-360 lycoming. Dropping cylinder off to be overhauled Monday but just curious as to what could have cause it. There was no marks on piston to indicate that the valve hit the piston and I have about 75 hours on the engine since overhaul.
 

Attachments

  • BE34C797-A658-44A0-8DAE-462230202E1F.png
    BE34C797-A658-44A0-8DAE-462230202E1F.png
    776.1 KB · Views: 942
  • 47336DD6-EC3A-4955-BD1A-AEC402A56CB0.png
    47336DD6-EC3A-4955-BD1A-AEC402A56CB0.png
    719 KB · Views: 942
  • F95E0E48-0696-4FD8-B39C-DF91F9CABC3A.png
    F95E0E48-0696-4FD8-B39C-DF91F9CABC3A.png
    768.7 KB · Views: 942
Valve seat is not ground correctly, the seating area is too far out to the outer edge of the valve face, the seating area should be central to the valve face, I will try to find a picture to illustrate it for you, the edge of the valve on the seat, with likely bad contact full circle of seat caused it to overheat and burn the valve.
 
Here you go.
 

Attachments

  • Screenshot_20200817-134111_Drive.jpg
    Screenshot_20200817-134111_Drive.jpg
    88.3 KB · Views: 890
  • Screenshot_20200817-133945_Drive.jpg
    Screenshot_20200817-133945_Drive.jpg
    117 KB · Views: 890
Back
Top