XXC

Can a clogged oil pump cause tapping noise from the valves?

P Zero

I highly doubt its your actual pump thats clogged, more likely the pickup tube is. And it could cause valvetrain noise if there isnt sufficient flow. Only crappy thing is in order to check the pickup tube you gotta take off the oil pan. And in order to take off the oil pan you gotta remove the motor.
-P.

XXC

what if I run a cleaner through the engine?

Liquid_02

That sounds like lifter noise, as you described it as a tapping, if it is, nothing to do with the oil pump, just bad lifters