remove/clean carb (trash/water/etc.) use carb rebuild kit. let carb soak in carb cleaner overnite. clean all passageways with thin stiff copper wire. blow clean with compressed air.

check all fuel lines for cracked/deteriorated. install/use inline fuel shutoff valve if a fuel gravity feed setup. drain/flush all fuel with fresh.

Well, read my paperwork and there is a warranty for 2 years, but I find authorized service location. Gonna change gas first then follow up on that.

You are correct that engine should be warrantied for 2 years. But, there maybe a pickup and return fee it you can't get it to the dealer. Also, make sure all the filters are clean, plugs are clean, If not they will probably say the rough running maybe contributed to that and that may not be under warranty, thus running up the tab? I know you said 14 hours on the engine, but in extreme conditions warrant a 10 hour check of filters.

Today I drained gas and ran it through my generator which uses a 19hp version of the v-twin, even though that engine is 20 years old I couldn't help but notice how much smoother it ran. I then put a gallon of fresh 93 octane in the tractor, still the same, got to be vacuum leak or broken valve spring or something. Very leery of how warranty work will be handled. Will return to post results, meanwhile the grass still grows!

Well, if anyone is interested, got tractor back yesterday, 3 weeks! And it was....carburetor! Seems ok, we'll see. TTFN