I have a 54'' Bobacat(Ransomes) that has been sitting for about a year. I am trying to get it running so I can get rid of it. It was tuned up prior to it sitting. It is a Hydro. The mower will now start no problem but when I put the blades on or I put the mower out of neutral the engine will stop running. The carb is ok the throttle seems ok. There is a butterfly valve? that is right behind the carb that seems to be closing when the blades are engaged. Model number is Ransomes-930307 with a Kawasaki engine FH500V-ASO8. Any help in fixing or locating a service manual would help thanks.