Yet another question for you Cub gurus and experts out there...
1947 J-3 A65 family owned since 1951 just recently started leaking fuel from the carb breather down pipe. Running ethanol free Mogas and the occasional fill-up of Avgas when away from home base. Had carb work done less than a year ago in order to replace damaged parts as a result of ethanol fuel. Original carb float and needle replaced with plastic (delrin I believe) parts. Have never, in 50 years had a carb leak, then all of a sudden, fuel is leaking after shut down. Have tried leaving fuel shut-off valve in both on and off positions, and tried shutting engine off by mag switch as well as by cutting off fuel supply to carb, all of which result in fuel leaking from the carburetor. Spoke with mechanic and good friend, both of whom seem to indicate that carb leak is normal, and that I've been incredibly lucky to experience no leaking up until now. Is there anyone out there who can support my theory that I'm not incredibly lucky, and that this is not normal/no big deal?? The only variable between when carb didn't leak and now is the use of TCP, as a result of the insistence of my mechanic to use the additive to combat plug fouling/misfiring when using Avgas. Both parties I've consulted also seem fairly certain that the TCP is not the culprit, although I'm certainly not convinced. In addition to the fuel leakage (which seems to be getting progressively worse), I'm also now finding a substantial amount of moisture in the bottom interior of my cowling immediately following flights. The moisture is not fuel, and I'm about 99.9% sure it's water, which covers the carburetor, cowling and breather down pipes coming through the cowling. Can anyone speculate as to the source/reason for the moisture, and if so, would you be willing to assume that it could be causing what seems like a rougher than normal running engine and slight power loss? Any help/insight is greatly appreciated!!!!
1947 J-3 A65 family owned since 1951 just recently started leaking fuel from the carb breather down pipe. Running ethanol free Mogas and the occasional fill-up of Avgas when away from home base. Had carb work done less than a year ago in order to replace damaged parts as a result of ethanol fuel. Original carb float and needle replaced with plastic (delrin I believe) parts. Have never, in 50 years had a carb leak, then all of a sudden, fuel is leaking after shut down. Have tried leaving fuel shut-off valve in both on and off positions, and tried shutting engine off by mag switch as well as by cutting off fuel supply to carb, all of which result in fuel leaking from the carburetor. Spoke with mechanic and good friend, both of whom seem to indicate that carb leak is normal, and that I've been incredibly lucky to experience no leaking up until now. Is there anyone out there who can support my theory that I'm not incredibly lucky, and that this is not normal/no big deal?? The only variable between when carb didn't leak and now is the use of TCP, as a result of the insistence of my mechanic to use the additive to combat plug fouling/misfiring when using Avgas. Both parties I've consulted also seem fairly certain that the TCP is not the culprit, although I'm certainly not convinced. In addition to the fuel leakage (which seems to be getting progressively worse), I'm also now finding a substantial amount of moisture in the bottom interior of my cowling immediately following flights. The moisture is not fuel, and I'm about 99.9% sure it's water, which covers the carburetor, cowling and breather down pipes coming through the cowling. Can anyone speculate as to the source/reason for the moisture, and if so, would you be willing to assume that it could be causing what seems like a rougher than normal running engine and slight power loss? Any help/insight is greatly appreciated!!!!
