I was told that the earlier ones did have a spark plug in them, never seen one. Here is some pictures of the six cylinder engine I found nearby, maybe a 1927? Also found nearby a 26-27 packard car all that was left was the frame, rear axle, springs, alum. floor board, drivers seat, and firewall. I am posting the pictures of the engine. All this stuff is for sale. Maybe its all tied together. Dan