Oops!

When I was trying to adjust the valve timing, the engine did not turn over for a complete revolution - because I had checked it before installing the piston rod gland filling.  The gland fitting was further out when the filling was installed (of course!) and occupied the space needed for full movement of the piston rod and cross-head.  I now have to dismantle the engine assembly to obtain full access to the gland to check and re-adjust it.  I suppose this will be good practice,   :( .  The engine drops out of the car without much trouble.  I shall, hopefully, also learn to check everything thoroughly as I do the work.