OK, have took tappet covers off, and i *may* have found the problem, or at least one of them...
The photo is crap (off my mobile) but it has a round, stepped bit of metal wedged under the tappet adjustment screw !!
I have NO idea how it got there, and its wedged real tight, i've tried turning the crank to wiggle it loose, but its not working, and idea's ??
