2006 ExMark 19 hp Kawasaki. I know it’s old but, I guess the valve guides are worn or does this mower have valve guide seals like the cars I used to work on. It usually smokes upon start up until it clears the combustion chambers of oil leaked by the valve guides, then it smokes no more and really uses hardly any oil all season long. I’m just a homeowner and it’s not used professionally. Can you just buy valve guide seals and put it back together and alleviate the majority of the white smoke. It’s kinda white to gray smoke but smells oily. OR, can you buy valve guides and seals and still reuse the original valves? Is this something I can do at home or is it a job for a mower shop to replace the guides. Thanks