17.5 B&S cyl fills with gas if the choke gets closed for starting... I mean it fills the cylinder and the engine won't turn over... If I remove the plug and turn it over a few times at 0 throttle it all sprays out... Put the plug and restart mower at low throttle and it will start and run pretty good for about 5 or 10 minutes, then it starts missing, like it's flooded... I'M TOTALLY PUZZLED BY THIS ONE AND WOULD APPRECIATE ANYTHING THAT MIGHT HELP!!! It's my wife's little mower and she gets all upset, when her baby quits. Especially when the grass is still growing as fast as the weeds... Thanks... Tom