Replacing the starter on a Kawasaki 19hp engine. It is a one for one replacement so the mounting holes are the same. For some reason I cannot get the bolts to start threading. Either one. Been working on it for several days. I make sure the holes in the starter are aligned with the holes in the engine block but I can't get them to start. I tried starting the bolts without the starter in place and they start with no issues. Anybody got any suggestions?