I am in the process of re-building my head !! due to a headgasket problem. I have decided to go the whole hog and replace the camshaft as the oil bar had obviously got itself blocked at some point and has caused a couple of the lobes to wear.
Anyway the problem now is that cylinder 4 has no compression - this seems to be due to the inlet valves not fully closing. I know this because if you pour water into the valve bowl the water dribbles out of the valves. When I took the new camshaft off, I again checked to see if the valve problem was still there - guess what - it wasn't. Does this mean I have an oversized camshaft which is not allowing the valves to close properly or am I missing something else ????

You haven't checked the shims. You obviously have too large a shim in that valve.

Take a smaller shim, use your feeler gauges to get the gap, do the math and get the correct shim.

Cheers

SPD