You changed the plug and clean carburetor and filter Riding lawn mower still won't start?

Answer 1

I've been trying to follow up on this. You say you changed the spark plug and cleaned the carburetor and filter. Is this to say the filter was not replaced? Also, was the carburetor removed and taken apart for cleaning?The fact that you say the engine is hard to start (but does start) and that it runs for five miutes and dies leads me to believe the engine is not getting sufficient fuel to keep running. Probably also insufficient fuel for a good start - is the choke working properly?

Based on what I am reading here, if the engine dies after a few minutes, it is a fuel starvation issue. That can also cause hard starts. If the carb is a diaphragm type- check to make sure the gasket is on properly. There is vent on the intake manifold and the carb that MUST LINE UP! if the gasket blocks that, or they don't line up your engine will not run.

If the carberatuer is a float type, use manufacturer specs and the right gauge (usually available from a power equipment shop) to set the proper needle height. If the needle is set wrong or damaged, shaken harshly, or mis-installed the float will not be set at the proper height, and the bowl will not fill sufficiently, either flooding, or leaning out to the point that your engine will not run.

MOST IMPORTANTLY-For either type carb, check the gas cap vent. If that is clogged in a gravity system, atmospheric pressure will not push the fuel into the carb. Air fuel mixture will be too lean and the engine will not run. Check your fuel lines as well, any clog or crimp in those can cause starvation. I am taking a class on motorcycles and one of the pre requisites was a power equipment class. I have repaired many mowers with the exact same problem using those steps. Not a guarantee, but I would wager my money on that, it is the case 99 times out of a 100. Good Luck!