Guys,
I have a question - I over the last few months I have seen these streaks on my belly. The photo is of the bottom of the fuselage along where the spar connects the two wings.
I said fuel in the title but I am not 100% sure what the fluid is .. . as you can see it has a blue tint but doesn't evaporate right off like 100LL and there is a bit of grit to it dark specs.
My first step was to pull the cover off the tunnel - no noticeable streaking or leaks. I did have an issue back in March when I did my annual I found leaking around the stopper (not sure what you call it) screw in my stock Van's Fuel Valve. At the time I tightened and torque sealed - in my recent inspection there was no leaking here or anywhere else I could detect.
One other possible area for fuel was a leak in the Right Tank along the in board rib joint about 2 inches forward of the vent. Fuel from this leak flowed down, aft and inboard along the spar - gear leg. I repaired this a month or two ago and cleaned everything up. There is no indication of fuel leak now - though I pulled the tank to make sure there was no leaking along the spare and found zero indications of a leak - also performed a pressure test no bubbles and it held pressure no issues.
One idea is that there might be fuel mixing with the grease from the gear leg??? But I don't figure out why the streaks would only be at the center of the aircraft and not all along the belly leading out to the streaks in the center.
I have a question - I over the last few months I have seen these streaks on my belly. The photo is of the bottom of the fuselage along where the spar connects the two wings.
I said fuel in the title but I am not 100% sure what the fluid is .. . as you can see it has a blue tint but doesn't evaporate right off like 100LL and there is a bit of grit to it dark specs.
My first step was to pull the cover off the tunnel - no noticeable streaking or leaks. I did have an issue back in March when I did my annual I found leaking around the stopper (not sure what you call it) screw in my stock Van's Fuel Valve. At the time I tightened and torque sealed - in my recent inspection there was no leaking here or anywhere else I could detect.
One other possible area for fuel was a leak in the Right Tank along the in board rib joint about 2 inches forward of the vent. Fuel from this leak flowed down, aft and inboard along the spar - gear leg. I repaired this a month or two ago and cleaned everything up. There is no indication of fuel leak now - though I pulled the tank to make sure there was no leaking along the spare and found zero indications of a leak - also performed a pressure test no bubbles and it held pressure no issues.
One idea is that there might be fuel mixing with the grease from the gear leg??? But I don't figure out why the streaks would only be at the center of the aircraft and not all along the belly leading out to the streaks in the center.
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