Small Engines (Lawn Mowers, etc.): Troy-Bilt TB475SS wont start, crank case, combustion chamber

Question
Hi Eric,
I have the above mentioned trimmer, TB475SS 4 cycle.
It refuses to start.
Replaced carb, cleaned or replaced filters and exhaust screen,
Replaced the plug, changed the oil, checked compression, reading of 60 PSI. MTD tech says that's normal.
Checked valve clearance, both at .004.

I did find oil in the combustion chamber.
I think someone over filled the crank case.
Checked spark, and it does get fire.
Checked the flywheel for a broken key, it's fine too.
All appears to be good.

Still it won't even attempt to start even with gas or starting fluid either in the plug hole or through the carb.
Not even a pop or sputter.

I'd appreciate any ideas.

Thanks,
Chris

Answer
I would try another brand new spark plug...I have had new plugs out of the box not work.

How old is the fuel?  Will the fuel burn if you try to light it with a lighter?  I use a screwdriver, dip the screwdriver tip in the fuel, go out side and try to light it.  I have found gas that would not even burn when lit with a lighter.

Eric