I know these engines well as I have two of them, but both have Tillotson carbs and the Tillotson carbs are junk. I have a rebuilt Walbro that I am going to mount soon so that I can get going again.

I know that the timing is different between the HP's for engines with Tillotson's as my first 25hp started out as an 18HP. That motor is a Frankenmotor.