Originally Posted by Frank Jackson
I should have looked at this sooner. Yesterday the #2 exhaust valve on my Lycoming IO360 stuck completely and bent the pushrod. Fortunately I was in the pattern at a nearby airport and immediately landed. It's now at the FBO at the same field getting a rebuilt cylinder. It had been running rough at idle and low power settings but smoothed out at runup power and higher. The engine had only 380 hours on it. I'll be doing a wobble test on the other cylinders.
I'm like you. I never paid attention to this post until your write-up today, because it happened to me this week.
My factory-new-plus-400 tach hours IO-360-M1B suddenly got rough under 1350 RPM along with an associated total drop of EGT on cylinder #4. I immediately showed it to Randy Richmond (aka Monk, our local 52F totally awesome expert of everything RV). He ran a compression check (there was none....0 inches, with a loudly audible hiss from the exhaust pipe). Diagnosis: Stuck exhaust valve.
Apparently, many (most?) mechanics will simply tell you the jug must be removed and sent to some repair house somewhere. Also, apparently, few will take the trouble to work the problem on-engine, if it can be properly worked on-engine. Randy actually conducted something akin to endoscopic surgery to clean the valve and inspect the pushrod.
All is Code 1, no bends, compression is good, and a cleaner valve. Of course, if the bits and pieces showed anything beyond mere carbon (or other gunk) buildup causing the stuck valve, he'd have elevated the level of repair.
I can't thank Randy "Monk" Richmond and Richmond Aviation enough. KELLI GIRL flies again!
Sid "Scroll" Mayeux, Col, USAF (ret)
Northwest Regional, Roanoke TX (52F...home of DR's Van Cave)
"KELLI GIRL" N260KM RV-7A tipper, YIO-360M1B, dual SkyView, GTN-650, VPX, EarthX LiFePO.
Wrap by AircraftWraps.Com. Nose Art by VictoryGirl.com.
90% done, 90% to go...
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