I have a craftsman lts 2000 Model # 917289101 with a 20 hp briggs and Stratton Model #331777-0946-B1,I start it up and use it for approx.15 to 20 minutes and it will start to sputter and try to die,if I turn the mower deck off it will catch up with itself and run. Here is what all I have completed on it, I took carburetor off clean it and reinstalled it,I did an oil change,I replaced fuel filter,I replaced spark plug,I cleaned flywheel magnets and coil (very rusty lookin) I tried loosenig the fuel tank cap I went to high test fuel and still no difference. Anyway you can assist me in resolving this issue I would greatly appreciate it
Thank You
Sounds very much like a fuel blockage.
Start with the fuel tank drain remove and clean it out.
good chance you will find a plug of debris in the outlet which will not allow fuel to flow fast enough when the throttle is wide open under load
