The more likely scenario would be that there is no spark for some reason. An easy test would be to crank the engine after shooting a burst of carb spray down through the air intake with the filter removed. If it tries to run, that would at least tell you that you have compression and spark. let us know what happens. Any model numbers or history you would care to share?

We put fuel straight into the carb and it will start and run until the fuel is gone from the bowl so we know it will run for at least a few minutes. Model number is 13AO672G129,serial number 1E292B40272. We have not used the mower since last fall, we have lawn service during the summer months for mowing so we use yard machine to pickup leaves in the fall, which is why we are trying to get it started. We will try your suggestion next. Thank You

It would seem that you have a fuel system problem. Fuel should be fresh. Flow verified to the carburetor. If there is an anti backfire solenoid at the base of the carb, check that it operates when the key is turned on. If all checks out, sounds like the problem is inside the carb.

New carb. Hmm maybe a leaking manifold gasket. Sounds like it is sucking air.

check air breather hole in gas cap! If machine has been setting for a while, little bugs like to lay their eggs in that hole, which plugs it up, which in turn, creates a vacuum in the tank, and fuel won't flow down into carburetor bowl--hence no start! A common problem, usually found with engines that set a while, not being used. Solution? Stuff a couple clothes dryer sheets around the engine. Bugs hate the smell. All of my machines get this treatment every fall, upon storage.
Also---bugs like to eat the spark plug wire insulation, with the spark shorting out to the block, and no start. Mice love to crawl up in the shroud, too, and eat the insulation off the wires, and build their nests where they will be safe from interlopers! RJ

Your fuel is probaby too old. I would drain the tank all the way to the carb bowl and use fresh gas. Loosen the bolt on the bottom of the carb to get all the old fuel out and flush a little fuel through. If it doesn't run, then the carb jet is gummed up. Also check for a mouse nest in the engine if it's been sitting that long.

When the lawn mower engine won't start that may be cause from the the carburetor. If it need to change a lot parts, you should buy a new one. Because you couldn't know what part will break next.

Here is a link that might be useful: http://www.bestsellingreviews.com/Garden/Lawn-Mower/

This post was edited by AshleyThacker on Tue, Dec 16, 14 at 1:19