Sometimes the intake pipes on Lycoming engines can come loose. This will cause an intake leak, usually indicated by a rough idle and higher EGT on the affected cylinder. The leak will also leave a tell-tale sign of dark material around the pipe from fretting. It takes a special internal swaging tool to reseat the pipe.
In Case You Missed It
“Glare” Shield
The body of this month’s column is part informational, part confessional and part Zen...
Firewall Forward: Cowls, Baffles and Intake Air
How to keep your engine’s carburetor or fuel-injection system breathing right.
Lancair Evolution
Lancair Aircraft is revolutionizing its already successful turboprop line of kits with the new Evolution, a 750-horsepower, Pratt & Whitney-PT6A-powered, carbon-fiber composite, 380-mph four-seater to be available later this year.
I had loose intake pipes starting around 1000 hrs. Tried some proseal around there which worked as a stopgap but eventually I found an engine shop that was willing to loan me the swaging tool. Lucky! Now all tight and good.