B&S 17.5 hp 311777 0120e1 engine problem

[pecanguy]

My 17.5 hp engine cranks and idles good. But when I increase the throttle speed, the engine begins to spit and sputter. When under load (with the mower deck engaged ) it is even worse. It seems to be flooding and spitting back thru the carburetor although the choke assembly does not appear to be closed. I thought it may be a valve problem so I pulled the head, valves appeared ok, lapped the valves, reset valve clearences to specs, and installed new head gasket. Installed a new plug. Replaced fuel filter. Tore down carburetor for the fourth time and soaked all parts in carb cleaner. I reused all gaskets as they seemed to be ok.
Carb rebuild kit ~$40.00, new ebay carb ~$100.00 ( maybe less ).
Is it possible that it could be out of time due to the flywheel key ?
Has anyone experienced this?
Any suggestions. Please. Any help would be appreciated.

 

[ILENGINE]

Remove the nut/bolt from the flywheel and look at the key. Should be a square. Offset indicates sheared. Also pull the dipstick and smell the oil to make sure there isn't gas in the oil.

 

[pecanguy]

Ilengine
I just checked the oil. It looks and smells like oil. (Up to the full mark) nothing suspicious.
I'll check the flywheel key tomorrow.
The mower was running fine until it ran out of gas. After refilling, it started spitting and sputtering. I drained the fuel tank and replinished with different fresh fuel. (No change)
Thanks.

 

[ILENGINE]

You didn't say anything about running out of gas before the problem started. I suspect that you have picked up the sediment off the bottom of the tank and now it is sitting in one of the carb jets.