"knocking" sound in new engine?

[Dennis List]

After months of work on the engine, we installed it again and finally could start it for the first time. HAppy as we were, all went well with no leaks and the engine seemed to run very smoothly. Valves were properly set, as well as the 123 Ignition.

Specs:
an original 602 engine block, a race ground cam shaft from Kent Cams, 9.0:1 pistons and barrels and original cilinder heads. Original flywheel with new flywheel bolts, brand new clutch.

We let the engine run approx. 2000-2500 rpm for about 20 minutes and it never gave any strange sounds and did not hold in.  We dropped it to stationary and it purred like a kitten. Then we turned it off and started again a few times (started immediately every time).
And now, the engine makes a knocking or rambling sound which requency increases with the revs.
I've checked the valve clearances again and re-set them with a barely warm engine. After this, the sound had not gotten less, i would even say it got louder.

I made some video's and i would very much appreciate if you guys could tell me what you think this is!

Video 1: Engine first start (mind that the exhaust is a leaky)
http://www.youtube.com/watch?v=Wv7nUfLmy6k

Video 2: Running in at 2000-2500 rpm and going stationary
http://www.youtube.com/watch?v=NaU7wKVMG8I

Video 3: Starting engine and knocking sound in the engine at stationary
http://www.youtube.com/watch?v=Tq7tw-eJxfY


Thanks!

[spanners]

Dare I say it-could it be a similar problem to this one? ???

http://www.2cvracing.org.uk/forum/index.php/topic,1280.0.html

[Dennis List]

It was the flywheel that had come loose. the new flywheel bolts seemed to have gotten loose. We tightened them again with great care and the sound had gone. Tomorrow i will finish putting all things together and make the first official test drive!!! Very Happy Thanks for your support on this!

[spanners]

Phewee! 8)

[Dennis List]

That's what i said too  :D

[Roy Eastwood]

On the subject of flywheel bolts, there are some around which are too long, ensure that the correct length is 26.5mm below the head.

It was the flywheel that had come loose. the new flywheel bolts seemed to have gotten loose. We tightened them again with great care and the sound had gone. Tomorrow i will finish putting all things together and make the first official test drive!!! Very Happy Thanks for your support on this!

[Dennis List]

I did use "new type" bolts, with round heads and a hexagonal hole in it (imbus). So far i've driven 135 kilometer without the flywheel coming loose again (no knocking sound for sure).