Hi PeterM279, and a warm welcome to the forum.

it's great to have another Rover Model 45 owner on board.
My first question here would be...what caused this? Was the drive roller clutch out of adjustment?
However, to put things right, here's what I would suggest:
(1) Order a new drive clutch cork...Click
HERE (2) Remove all chains and sprockets, including the inner half of the drive clutch, and thoroughly clean the chain case area.
(3) Thoroughly clean the inner half removing all traces of old cork and glue by carefully scraping and a suitable solvent....(Methyl Ethyl Keytone (MEK) is great if you can get it).

(4) Obtain the glue....here's a pic...This is of the cutter clutch, but the procedure is the same for the drive clutch.
![[Linked Image]](https://www.outdoorking-forum.com.au/forum/uploads/usergals/2013/09/full-1147-12614-clutch_cork_glue.jpg)
(5) Replace the cork, carefully following the glue instructions perhaps using a piece of board and some clamps to hold it in place until completely set.
(6) Clean all chains and sprockets, inspect for serviceability, lubricate and reassemble.
(7) Adjust the drive clutch
Happy Mowing.