I got a yth2348 husqvarna mower and the valves were way out of spec. so I readjusted them to .005". It ran for about 30 seconds just fine and went to the same old popping and hard to start. So i went back to adjust them and they were off again. Its on a Intek 23 hp Briggs. Im stumped on why it keeps moving. So if anybody could help me?