Small Engines (Lawn Mowers, etc.): Lawn tractor with b&s engine stalling, murry lawn tractor, hp briggs

Question
My next door neighbor has an old Murry lawn tractor with a 12 or 12 and 1/2 hp Briggs engine on it. Recently it began to run awhile and then stall. He said it cranks back up and will go a little further and stall again, and would crank back up. He asked me to help him, but I know very little about riding mower engines. I told him it sounded like it might be a carb problem, but I don't know what to do about it. I would appreciate any input you can give as to what might be the cause of this problem as I know very little to tell him. Any suggestions would be greatly appreciated.  Stephen

Answer
Hi Stephen
 It sounds like there is a fuel blockage. Check the fuel filter if there is one and also check the fuel tank for trash that could be blocking the flow. If that all checks out, the carb needs to be removed and cleaned making sure that all jets and ports are open. It also wouldn't hurt to replace the needle valve. Hope this helps.