I have a John Deere 855 i use for mowing with a 72" belly mower on it. The tractor is in good shape and it start up as soon a you turn the key and runs great with 1706 hrs on it. i dont know if im just being paranoid since i love this little tractor but it smokes white when its cold and until it warms up. Not a lot but enough haze to notice. Once its warm no smoke it runs clean. Just wondering if the injectors need tested or if its normal?