Last night I checked the tensioner as suggested by Tiger and Karl. It seemed fine. It moves freely and has 5-6 clicks left on the ratchet. I pushed on the plunger with about 100 pounds of force and it does not slip past the lock. The lock ring is of the new design per the factory manual.
I know that the noise is not the lifters because I put in the solid lifters from the 230CE and this did not affect the sound.
Any ideas?