Gasoline leaking from tank cap

[Charles67]

On all the Pitts that I have flown, factory and experimental, I haveoccasionally smelled gasoline during aerobatics. I finally determined that the gasoline was leaking from the cap of the main tank, afterin one occasion I actually saw a few gasoline drops coming out of the tank. If the cap is new or old, factory or aftermarket, made of fuel resistant rubber or not, does not seem to matter. And tightening the lever on the cap more seems to make things worse.Any suggestions or any recommended brands of caps to solve this problem?Thanks

 

[grassroots]

 

[Charles67]