Ben, have you tried presenting the car to a real garage, to see what their response is when presented with it?
Not yet, as there's no garages in Manchester that I know of that are reccomended. Closest was GolfNutz - but last I heard, they've closed down.
I'm not sure if this would affect it, but I still haven't replaced the rocker cover gasket, GSF were out of them, so I'm getting a new one on Monday. My current one is a little mishapen (not brittle/broke), along with this, my oil filler cap broke the other day and it seperated, I clicked it back together, but one of the pins snapped.
These two are getting replaced on Monday, but I'm wondering if they could be contributory?
As it ran for about 10 mins completely silent, I would be under the impression that the pre-primed lifters were doing their job, and we're sat at full extension? Then without sufficient oil flow/pressure, the hydraullic lock stopped and they compressed down?
I've got 20l of fresh oil in the garage and I don't mind doing an oil change again, or even running flushing oil through if its possibly a blocked channel issue.
Is there any way I can measure the cam lobes to see if they have been worn, same applies to the cam bearings?
Also, just to confirm, I torqued the cam bearing caps to 20nm - this is definately correct?