car all back togther this evening, took it out - running fine, big end knock (I know that's what it was now) gone, warms up fine, 20 mins later I'm ready to do the last stage on the headbolts.
check plugs first 1,2,3, great - 4 - oh crap, looks a bit black... look down the bore to see the piston swimming in oil.
I know straight away what it is - no.8 bolt (front right) - the very same one that I helicoiled, has screwed up (pardon the pun) - I thought it didn't feel right going in but I put that down to the helicoil - when I got the bar on it, it turned far too easily, so basically that corner of the head wasn't torqued down right and the gasket has blown through - and sure enough there was a film of oil in the water - **** - why the hell the damn thing worked the first time I've no idea.
it's cooling down now - ready to have the head off again
I would just like to add that this engine seems like it's jinxed or cursed and it's a crapping big crap-pile of crappy crap that is crap, most probably pants as well
so who knows what needs to be done now, or when it's going to be ready again.
and finally - nuts.