Thanks Darryl, removed the clutch housing & presto, there was already a circumferential scratch around the shaft to show the location of the set screw as you mentioned earlier. I simply cut a larger hole in the LHS housing replaced the set screw (which now rests in the scratch), made some adjustments via the adjusting screw under the shaft & all seems ok now. Will monitor it after I next cut the lawn & if I have any issues will just go and buy a newie.
Thanks again for your help & advice here.
Cheers!! Ross
