I am almost positive one of the carbs has a plugged high speed jet, the fact that the sea foam showed some improvement indicates this. For those that don't believe in sea foams powers, I can tell you first hand while working at john deere dealer and seeing time after time just how well this stuff works. so the next time you take your mower or rider in for a carb clean and pay $85, they probably put some SF in a fresh tank of gas and let it run for a couple of hours. Our shop made a killing the first year the Gov made unleaded gas mandatory.
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