I have a mower that I let sit for about two years while I had a
gardener. Now I'm trying to use it again and it won't start. I
drained and changed the gas, cleaned the plug, checked the air filter.
I sprayed the inside of the cylinder and the carburetor with gumout.
When I pull the starter, the engine ignites the gumout and runs for a
few seconds, then dies again. So I'm guessing that means it is
getting a spark so it's a fuel clog issue?

Anyone have any advice? This is a Craftsman (Briggs & Stratton)
standup mower that has really only been used a couple of dozen times
over the years--it's just been sitting in the garage for awhile. I
live in Los Angeles so it's fairly dry here, but it has sat through
some very hot temperatures in the summer.