#4 and #6 cylinders on my 150 Franklin leak audibly past the exhaust valve. The guides have apparently belled out so there is notable "wobble" (see Lycoming service bull SB 388C for definition). I am almost certain that I need new guides. The 2 companies that I know of that might do this work are Southern Aero in North Carolina and Aeroworx in Alabama. Has anyone dealt with these companies? To have your responses stay private please send to email address markwdavisatlivedotcom. or text me at7202127275
I hear good things about AirWorx but I have not used the personally YET!
Had my '165 overhauled by Chris at Airworx.
Two thumbs up. Great, knowledgeable guy.