Hi guy's, so here's the deal. These engines run hot (105C). This is normal. The valve seals are not made of "viton" which take extreme heat (shame on BMW). In the UK it is easy to get replacement viton seals. It is a time consuming job, but very rewarding when complete. You do not need to remove the cyl. heads, just pressurize the cyl. with compressed air so the valves will not fall into the cyl. when you remove the valve spring seat retainers . It cost me $300 can.$ which included the cam cover gasket set which always leak. If you have a long distance phone plan and would like to contact me, I'll be more than happy to add more useful information. Just a reminder that I am 5 hours behind you in the UK. PM me. Ross.