Almost embarrassed to post this but i have bought three PCV grommets and cant get ant to seat into the pipe. The last was an OEM grommet for 2F engines. It will NOT seat into the pipe. The OEM grommet has a cone shaped bottom and if i feel inside the pipe there is a lip. The cone will not fit down over the lip. Another listed grommet was flat but it did not work either. What have you used that works? `The original is brittle and wasted.`````````````````````````````````````````````````````````````````