I have a 750 vac. sec. 3310 carb . I went to change the jet's for the first time and the threads came out with the jet . The carb is about a year and a half old . has this happened to ayone before and what do I do to fix it . If I can't I will have to get a new metering block.I was thinking of a set of Quick Fuel blocks so I could change the jets in the sec. side too .But if I could fix the old one I could take my car out a couple more times before the cold weather rolls in . wich isn't too long away. appreciate any help.