Forgive me y'all, yet another 'guess this noise thread.'

I check my tranny fluid level a lot, about every two days, someday I'll put in new seals and/or rebuild it. Anyway, I've been noticing a funny noise that fades in and out. It almost sounds like tapping a penny on glass, like you might do on a door instead of knocking.

The vid was taken at night, now and then you can see that I'm moving the phone about, but the intermittency in the vid is very much like it was to my ears at the time, which were not being moved about. You can hear it for the first few seconds, then again peaking at around 12 or 13 seconds, then again at around 25 to 26 seconds, which indicates a strange regularity of cycle.

Seems to be 8 clicks a second. That would indicate one tappet move per cycle, one piston, correct me if I'm wrong.

http://youtu.be/c21_xj4mesc

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