Anyone come across this problem with the above engine? Sounds like a noisy tappet, gets noiser with engine speed. Removed valve cover everything looks OK, removed camshaft and solid lifters/buckets. There seams to be a hard carbon deposit on the top of the valve spring retainers on 2-3 cyls where the noise is the loudest. Next step is remove cylinder head. Any common problems with these engine??

Many thanks.