BG400, the pilot jet(in my opinion) is easy to change. If you've never worked on a carb I suggest you visit your dealer. Here are some general instructions in case you want to tackle the job yourself.


In general: turn off the gas, disconnect the fuel line from the carb, disconnect the carb from the air box and intake(opposite sides) , then flip the carb upside-down and unscrew the float bowl, once the float bowl is off you unscrew the jets and replace, then put it all back together ... be sure not to disrupt float level while changing the jets.....

I do recommend buying the service manual, it's very helpful.