My 1250, purchased new in 1980 runs like a champ. Over the last year It started stalling after about an hour of use. It would try to start if I gave it full choke, but just ran very roughly then stalled again. I have rebuilt the carburetor, and having read some comments on Kohler engines have adjusted it on the rich side. Once it cools down, it runs like a champ again. Anyone have a similar problem and have a solution? I still haven't figured it out. My friend calls it the two beer tractor. Cut for a while, stall, have a beer, cool down, finish the job.