Small Engines (Lawn Mowers, etc.): Lawn Mower wont start, briggs stratton, fuel tank cap

Question
Before I get into cleaning out the carb, etc...

Briggs & Stratton 4.0hp Engine (in a Murray Select 20" Push Mower)
Model: 10A902
Type: 2291 B1
Code: 02062651

She sat all winter, not 'winterized' as indicated in manual.
Trying to get her going. Fresh fuel, filled oil to spec., cleaned out Air
Cleaner/Foam Element/oiled, primed and pulled, etc.
Can't get her going. So I realize I have other things to look at. But, in this
process, before I start pulling things apart...

My question is, would the position of the Governor Control Lever have to do
with her not starting? No throttle, carb is not adjustable on this model. Not
sure if the Governor Lever needs to be pushed all the way to the right (when
facing it) as it kind of locks into place against the engine. What is the purpose
of it and should it be moved?

Many thanks.

Engine in

Answer
Suzanne

Possible causes:

Fuel tank is empty or shutoff valve is closed, or fuel line or fuel tank cap vent is clogged.
There is water in the fuel.
Carburetor is overchoked.
Carburetor is improperly adjusted or needs service.
Ignition system or its wiring is defective or ignition switch
is off.
Deadman or other cutoff switch is open or defective.
Spark plug is fouled, improperly gapped, or damaged.
Engine compression is poor.
Operator needs to read user manual. :)

Problem: Engine operates erratically, surges, and runs unevenly.
Possible causes:

Fuel line or fuel tank cap vent is clogged.
There is water in the fuel.
Fuel pump is defective.
Governor is not set properly, sticking, or binding.
Carburetor needs adjustment or service.
Loose carburetor/intake pipe resulting in vacuum leak