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Smaky · 01-08-2008

You've got my thinking exactly there Sy, the best of the pictures is yet to come, the #8 lobe on the exhaust cam had me thinking it was a bearing when I had a quick glimpse the first time, it is almost perfectly round (had to do a double take as I couldn't believe the wear) the surprising thing was that apart from this chatter at @2500 rpm there is no other symptoms, there's a bit of smoke but it actually smells fuelly so I think the Lambda may be dead, other lucky things we found las night were that we suspect the balance belt wasn't on correctly (there are white marks that don't line up with the timing, not a big problem though) and then there was the Exhaust cam pulley, which had the location peg missing, this was so close to being refited that it caused a stir, and a "oh christ do we have a spare???" moment. We did, an hour later (and a few stellas) she was purring again, the variator was silent (more luck than judgement on the choice of bits to build it), the tick over is gentle, quite and steady, the acceleration is steady and undramatic till 2500 rpm, when that infernal noise returns, carry on through to @3000 rpm and the noise goes and no more sign of it at all till the red line, accelerate aggresively and there is no noise at all, studying the entire build up of the engine and using my built in sonar, the noise is certainly from the mid area at the back of the engine, tonight the balance belt comes off and hopefully that will be definitive.

In this blury pic (I appologise)you can see lobes 7 and 8 of the exhaust cam and an opend variator.