Murray Riding Mower with Briggs 11hp will not start

[hannachris]

The oil is mixed with gasoline I removed the filler neck completely and about half a gallon of oil/gas mixture came out.
The engine didn't rotate fully counter clockwise, just about 1 turn then stopped. Starter motor appears to be fine.

Thanks

If oil comes out of the filler neck then there was too much in the crank case.
Oil level should be just below the hole in the crankcase once the rubber grommet that seals off the dip stick tube is removed.

Now you say the engine rotated counter clockwise but not clockwise ?
Or the starter motor rotates one way & not the other.

If the starter is not jambed into the flywheel the motor should turn in either direction with roughly the same effort.

 

[bertsmobile1]

Well that is very sad news for your engine.
As the Queen of Hearts said to Alice
"OFF WITH YOU"

Me thinks you will find a bent / broken rod

 

[hannachris]

So today I drained the oil. I cannot turn the flywheel by hand now. I took off the cylinder head because, hey, what have I got to lose at this point? Might as well try and learn. Smaller valve is stuck out and cannot be pushed in. Bigger valve is flush with block and will not move either. Piston was able to be pushed back with minimal effort.

I'm sure this is shot at this point.

Well that is very sad news for your engine.
As the Queen of Hearts said to Alice
"OFF WITH YOU"

Me thinks you will find a bent / broken rod

 

[bertsmobile1]

Well the stuck valve will prevent the engine from being turned over.
The engine may be economically recovered.
It will all come down to the state of the crank and the bore,
So flip it over and pull the sump