help!! Weird sound

[LeSeb]

Hey everyone. Having a weird situation on my M20
It has a intermittent knocking sound. It doesn't sound in sync with the motor.
When I use a stethoscope it seems to be coming from under the timing cover.
I removed the top thinking my tensioner was the problem but I found nothing.
Any ideas?

Link to video

Check out this video on YouTube:

http://youtu.be/gLwutcabwk8

[estoguy]

Have you done any work on the engine recently? Forgot a nut or bolt?

Also is the engine cold or warm when you took the video? My M20 does knock a bit when it's cold.