So - the story so far - confirmed oil in the combustion chamber, and I've now stripped down the head.


There was evidence of a leak on the valve seals and some obvious signs of the seals being damaged, so they definitely need replacing. I'm taking the opportunity to give the head a good clean whilst it's apart and have been checking the tolerances against the manual specs.

My valve stems are both about 7.94, which, if I'm reading this table correctly, makes them within tolerance, but there's something funky going on with my intake guide, which appears required some persuasion to extract the valve from it. So - I'm thinking that it might be worth my while replacing the valve guides.
@themoudie - Bill - I see you posting a while back about K-liners (here: viewtopic.php?f=3&t=3717&p=29676 ).
Knowing that you're just up the road from me, I wonder if you might share who your engineering company was for this? I'm guessing that they would bore the existing guides to fit the liners? - should I consider fresh valves also?
I'm also a bit surprised at the specs given for the piston rings. They don't seem to tally at all with what I have installed. I suspect my piston is probably not OEM. I think the table is suggesting that the 250 Monza doesn't have an oil control ring, but I do. Furthermore, the ring gaps when installed in the bore is 2mm, much more than the tolerance suggested in the table.
Interested in views out there by those who know more that I do..!


Thanks,
Mike