I have clubcadet 1525 that will start when choke is on and run for few minutes until I release the choke .checked linkage and cotrolls everything g looms I. Good shape
First check air & fuel filters for replacement, fuel tank cap vent open, not plugged with dirt etc., & if that does not help it remove, clean & inspect carburetor thoroughly, you may need to purchase carburetor overhaul kit. Post all numbers from engine & engine manufacturer, thanks.
Sounds like an intake leak. Check the bolts that attach the carb to the intake and the intake to the engine. If they are nice and tight then do what Mark said. I always try to start with the "free and easy" stuff first then work my way up the price ladder.
Tom