I would guess they are plastic. I have never done this because I sold my 40. What I was thinking is get a short piece 1/8 inch of teflon tube with the same ID as the idle fuel hole. Drill out a short section of the hole to fit the OD of the tube and press in tube. Plastic might work too as long as it is gasoline resistant. There is no reason it can't creep out of the secondary transition slot, but I haven't seen it happen.
I'm not even sure it is creeping out. I just coculdn't find any other reason that made sense.
I'm not even sure it is creeping out. I just coculdn't find any other reason that made sense.