Leaky Fuel Injector

[CFI1513840]

Just after shutting down, I noticed a occasional "sizzliing" sound coming from the vicinity of Cylinder #2, lot a drop of water on a hot griddle. I removed the top cowl and inspected the fuel line and injector for #2 and noticed a black sooty residue around the base of the injector. Is it possible that fuel is boiling out of the injector vent and causing this? There is no residue around the other injectors. I removed and inspected the fuel line and injector and everything looks ok. I'm not sure if it is even a problem at this point, but wondered if anyone else has experienced this condition.

[g zero]

Check the location of the "A" stamped on one of the flats of the injector , Lycoming recommends that it faces a defined position . I can't remember if it is supposed to be up or down .

[g zero]

Just checked , "A" goes down .

[erich weaver]

I have a sizzling sound after almost every flight. It's residual fuel boiling in the fuel injector lines. Normal in our tightly cowled planes, and also associated with a rough idle that is commonly observed after touchdown, when there is little to no cooling air. I also have black sooty residue around my fuel injectors. If you disassemble them, you will see that there is a screen present in them and they are not sealed from the atmosphere; they are never pressurized. It stands to reason that small amounts of fuel from the injection lines exit this area after shutdown, resulting in the staining. Direct your worries elsewhere, all is good with your injectors

Erich

[Lars]

What they all said. Adding to that, when pressurized fuel stops flowing to the flow divider, there is a spool inside it that positively shuts fuel off to the nozzles. Residual fuel in the stainless steel lines can boil off, but there is no additional fuel being supplied to the nozzle.

[CFI1513840]

Thanks for the replies. I can worry about something else now.