First off let me say that I am not very mechanically inclined. My 7 year old MF 2300 is suddenly making a very high pitched noise when I first start the tractor. It sounds like a rotational noise and appears to be coming from the forward end of the engine. When it first started about a week ago it would stop almost immediately and seemed to be fine. The last few days it seems to be lasting longer but still seems to stop abruptly. I have no idea what it could be but any suggestions would be helpful.