Why not just come to an understanding on what is an acceptable amount of overtime. Then once that limit was reached for the week it would be understood that you would come it late however many hours you worked over the day before. This will help your boss to know exactly what to expect in overtime and still give you the opportunity to get some overtime.
If that doesn't work, as others have said, it may be time to move on.
If that doesn't work, as others have said, it may be time to move on.