Thanks Benzmac and Vinimg. Checked the fan shroud and nothing out of line there. Also, put a wood stake on the end of the tensioner shock as suggested, but, the tapping stayed. One additional item - the tapping noise starts about 1 minute after engine start and stays until the engine warms to about 1/4 of normal. It does seem to be more in the area of the timing chain cover. Guess I'll have to get a stethoscope and listen.