What type of aircraft? are the carbs and manifolds swapped to the outboard position like a Kitfox 4?
maybe the carbs are shaking too much?
Are the pneumatically carbs synced at idle?
Idle too low?
Engine mount weak (not containing torsional vibration)?
Hi Roy! Did you ever get this problem solved? I am having nearly the exact same issue. Carb vent lines are leaking fuel after carb rebuild. Floats are within specs and they float, also replaced viton tips in both carbs.
We thought we fixed everything and got thru a carb sync and everything ran perfectly for 10 minutes. Started up the next day for a test flight and the engine ran rough and then started leaking out vent tubes again!!
This may be the float brass armature is not adjusted properly or the needle valve isn't shutting off the fuel. I have saved several carbs from this by polishing the needle valve seat.
Roger Lee LSRM-A & Rotax Instructor & Rotax IRC Tucson, AZ Ryan Airfield (KRYN) 520-349-7056 Cell
Ian, just a thought, have you double checked the bowden cable and housing installation. If the housing(s) have leeway to move even a little you get all sorts of vibration despite a preliminary good sync - it just won’t last. If the housings are not firmly fixed (with no leeway) syncing carbs is a game one cannot win.
This website uses cookies to manage authentication, navigation, and other functions. By using our website, you agree that we can place these types of cookies on your device.
You have declined cookies. This decision can be reversed.
You have allowed cookies to be placed on your computer. This decision can be reversed.
Login
This website uses cookies to manage authentication, navigation, and other functions. By using our website, you agree that we can place these types of cookies on your device.
