i went to start my tractor today and the low coolant level light came on. i shut the tractor off and checked the coolant resevoir and it was at the low mark. since there was no obvious extermal leaks i pulled the oil dipstick and the coolant was right to the top. im assuming ive got a blown head gasket. the engine has never overheated and always ran well. any insight would be appreciated. is it an overly difficult job to do? not sure how im going to get it in my shop as the loader is down and i dont want to run it and wash out the bearings. hopefully i can push it in in neutral somehow.