Use the aftermarket inline petcock from Motion Pro:only thing i miss about the petcock is being able to turn the fuel off when i changed out my inline filter
My petcock was leaking the same as yours. My o-ring was bad. I went to O'reilly auto part store and found a pack of 9 for $3.99
The number is 64462 Metric O-Tite!
The bar code # is 37495 64462. These fit perfect. Hope this helps!
Do you know the dimensions of the o-ring that you got from o'reilly?