i am looking at trading my 2 stroke for a crf450 but the guy who has it says that the water pump leaks a little bit, he said it leaked before and he replaced the water pump and gaskets and everything but it still leaks a tiny bit, he said he may have damaged the gasket or something when he put it back together, i dont know much about this stuff so my question is, is this an easy thing to fix or could there be more problems that are causing this???