I thought that tube was not designed right having no shank to seal like most other fittings do. I'll add that tie down. On close inpection I also found that the needle valve stop clip was very lightly stopping the needle valve. The needle could have been turning but I think the tube is probably it. The plane it was on crashed and I layed it to rest in the garbage can so the engine is up on the shelf. Now I have rolled out the WM Super Sports 40S with a Super Tigre .51 Ringed. Excellent engine it has so much power on that plane it makes the .40 LA Look like a .10. I was told Super Tigre wasn't very good but after using one Wow! It will practically do vertical manuvers with that engine.