How long have you been using your tractor? If it is quite old and you use it often, there is a chance that some mechanisms are no longer working as you would like and not as they should be. You'd better call an auto mechanic and find out the problem. After all, if your sewer pipes are clogged, you will contact the
drain cleaning service and will not try to solve the problem on your own until the need to attract a plumber becomes obvious. Right now, it seems obvious to me that it is necessary to involve an auto mechanic.