RedGreenGuy
Member
Have an early 1955 TO35 I am reassembling after major teardown. Have replaced the exhaust manifold with new one from this site. Down flow exhaust pipe connection had adapter I removed to accommodate new exhaust pipe. 3 bolts holding on adapter were counter sink heads. New exhaust does have that feature, so am trying to use 7/16 NC thread to install new exhaust pipe. This is correct bolt and thread according to parts manual. Bolt will start about 2 turns and then resists further turning. Have tried finger inserting a 7/16 tap. It also stalls. Should I force the tap? Got me puzzled.