I've noticed that when I park my plane and it's not level the fuel tank vent will drip fuel. The obvious fix is to park the plane level, but thats not always possible.
Does anyone have any suggestiones to help fix this problem? One thing that comes to mind is fabricate something to plug the hole while on the ground and mount a red flag to it so it doesn't get forgotten.
I wonder what effect turning the fuel selector to OFF would have on this.
You didn't mention what plane/year that you have, but if it is like my 182P, 1972 model, there is a vent line going directly into the top left end of the fuel cell (bladder) with an upward offset inside the tank with a flapper type valve attached to the end. The valve is to allow air (vent) into the tank during flight, but flap closed on the ground as to not leak fuel. There is a seperate line nearby that goes across through the top inboard wall of the tank across through the forward headliner space to the opposite tank. There is no valving in this line.
Your valve is most likely not closing properly (common) and allowing the fuel to backflow out of the tank. If the offset in the line is not positioned to the top of the tank, even more fuel can leak out.
You can:
park with the vented tank on the upper hill side.
put a wood/plastic/concrete ramp pad under the left main wheel.
not completely fill the left tank on refueling.
remove the two bolt circles of screws on the filler cap and remove/fix or replace the valve. This will probably require a new gasket to reseal the top of the fuel cell.
Plugging the vent probably is not the solution except for large quantities of fuel as removing the plug will allow all of the volume of the vent tube full of fuel to escape when it is unplugged.
The fuel selector has no effect on the vent system.
The fuel that is coming out is expanding from being heated. This is normal. I would not plug it! We put the selector valve in either the left or right position to prevent crossfeeding during fueling. Cessna's
The vent "check" valve on the metal tanks, resembles a flapper valve that acts as a check valve. This valve must be oreinted correctly when installed. There is a hinge that the top of the valve that if not positioned at the top or upright will cause fuel to leak out of the wing vents as this is a gravity actuated closed valve. In hot weather these do pass some fuel but should not pour, and the rubber on the seal of this valve, when worn, will also be evident at the wing vent...
