I have an older Craftsman push lawn mower with a 5hp Tecumseh engine that starts when you prime it, then runs for a second or two, just on the fuel from the primer. It worked great most of the way through the lawn, then I stopped it to pick some weeds, and when I started it again it started sputtering, exactly as if it was running out of gas. Now it won't start for more than a few seconds. I've changed the filter, the oil, the gas, and opened up the carb which looks pristine inside. I'm kind of at a loss here. Any ideas?

Hello, A friend of mine has asked to take a look at his Honda HR173 lawnmower. He said it was running great and suddenly stalled. He took to it to a repair shop who said the carburetor need to be replaced at over $200.00. I removed the carburetor and thoroughly cleaned it including all the orifices with a tag wire. I re-installed it. The mower runs at all speeds but not smoothly. The pilot screw is turned all the way in and if backed of begins to run even rougher. When slowing the rpm with the throttle control it takes a long time for the engine speed to drop if at all. Please advise. Thank you