I would add some Sea Foam Motor Treatment to give it that extra explosion when starting. It will also help clean the carburetor, fuel injectors, clean carbon, gum and varnish deposits.

Does it want to fire up if you squirt some carb spray in through the venturi? If not, my guess would be a blown headgasket or a sheared flywheel key. If so, you have carb issues. IE not priming due to a corroded bowl or gasket that doesn't otherwise seat.

I have thoroughly cleaned carb. all is good with that part I also installed new primer bulb and ring and replaced carb gasket for bowl. The fresh gas goes into the bowl I have absolutely co corrosion or deposits. The spark is strong with the plug. I found a plastic "L" shaped attachment going from carb to fuel line, I wonder if there is a possible in line fuel filter in side.

yes it wants to fire when I spray carb cleaner in carb. I will check that plastic "L" to see

with kill switch wire off. I have good spark. with kill switch wire put back on, I get no spark. what to do? thank you

Find the bare spot in the kill wire where it is grounding.

If it wants to fire with the carb spray, you would then have spark. I'm assuming this is a Tecumseh engine? Sometimes the arm/ mechanism that the cable attaches to gets bent to the side and that can give intermittent spark. So can a binding control cable.