JD1020 flooding

[heehaw]

I have a JD1020 gas tractor, i've gone through 2 needle valve and seats; i found a small indentation under the seal of the seat the last time, about the size of the end of a straight pin and 1" long, so i put some sealer on the gasket, the sealer with copper floating; it worked very well for a while, then sunday night a potential buyer stopped by, it started well, ran great, it was sittin there idling while we discussed price and it started belching smoke again and right back to flooding again..i hope, the sealer i used isn't recommended for gas?? i'll check tonight; lost that sell though..
heehaw