Gas in oil sump Briggs and Stratton Engine

[Tonyclo]

I have a Briggs and Stratton 21HP V engine. Cleaned carburettor replaced seals, checked float and needle, checked fuel cut off solenoid (it works). Checked compression and found 175 lb/sq" both cylinders. Engine runs smoothly with lots of power. I am totally baffled as to how the gas gets in while I am running. Does not get in when not running. Appreciate any ideas.

 

[mechanic mark]

Post tractor model number from under seat as well as all numbers from engine data plate, thanks. You need to purchase correct B&S carburetor overhaul kit, clean & install new kit or purchase new carburetor. Some kits are almost as much as new carburetor.

 

[Tonyclo]

It was the fuel pump. Replaced it and no more problems. Gas goes down the tube connecting pump to the crankcase if the fuel pump diaphragm is perished.

 

[mechanic mark]

Good deal, pat yourself on the back.