Twice I got over filled on the inner tanks... enough that leakage was coming out after the plane was in the sun. In both cases I saw a oily residue on top of the aileron after the aircraft was flown. See pictures.
The residue had a yellowish greenish hue to it... oily but itself somewhat volatile. It was evaporating slowly after 30 minutes or so (at 75F). No blue color at all. It appeared to be coming out near the fuel vent area. I disassemble the vent cover, looked inside and all vent hoses were intact and no residue was inside there. The fuel line was dry and I saw no other lines nearby.
To worry? I'm thinking this is just decades of fuel residue/varnish/volatiles that accumulated that the overflow perhaps knocked loose and it came out once I was airborne.
Bottom side showing fuel vent.
Top side showing residue coming up and streaming back on aileron. Quarters for sizing, and green painters tape for location.
p.s. As an aside, it looks like the Aztec would benefit from Aileron gap seals as almost all the residue rose up through the gap from the bottom to top side... showing a significant air leakage path.
The residue had a yellowish greenish hue to it... oily but itself somewhat volatile. It was evaporating slowly after 30 minutes or so (at 75F). No blue color at all. It appeared to be coming out near the fuel vent area. I disassemble the vent cover, looked inside and all vent hoses were intact and no residue was inside there. The fuel line was dry and I saw no other lines nearby.
To worry? I'm thinking this is just decades of fuel residue/varnish/volatiles that accumulated that the overflow perhaps knocked loose and it came out once I was airborne.
Bottom side showing fuel vent.
Top side showing residue coming up and streaming back on aileron. Quarters for sizing, and green painters tape for location.
p.s. As an aside, it looks like the Aztec would benefit from Aileron gap seals as almost all the residue rose up through the gap from the bottom to top side... showing a significant air leakage path.
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