ryobi spares

I have a couple of ryobi 3046 strimmers, both of which are now just out of guarantee. both are broken with a clutch related problem. Does anyone know where to get get service manuals/spares etc. I've tried ringing Ryobi(tti-uk.com) but they dont answer the technical line. . . . I guess i should of spent the xtra and bought kawasaki

 

Thanks for the input. shoulders is helpful although I could do with a service manual for the clutch settings.
Cheers MF

 

Does it have a clutch?

 

yes, but its a very crude centrifugal clutch mutch the same as on cheap chain saws. So effectively when in tick-over the head isnt spinning but as the rev's reach a certain point the head begins to spin. All a bit meccano..ish