Mine dies too when I engage the deck, however I've found that if I give it some choke, it won't die. And I can stick with my old method of keeping engine RPM low.The last two X540's I have bought have been a real "PAIN". And I never will get used to reving the engine to start the deck. That is totally against everything I learned driving John Deere tractors for the past 65 years.
My next lawn tractor is going to be a Kabota.