I was wondering if there is a set time to grease my YM1700, don't have a manual of anykind, you know like so many hours? Also I have 4 foot bush hog, and no manual with it either. So far I have been just greaseing when I think, it may need it, kind of a hit and miss sort of thing. I was thinking there might be some sort of time hours of use, two or three times a year, or what ever.