Hello
Paul and Max,
The
400 was made as as chain and then as a belt drive.
You mention 'sprocket' which indicates the earlier mower.
A parts list is here: -https://www.outdoorking-forum.com.au/forum/u...rison-the-olympic-reel-mowers-c1962.htmlMax has also posted some info.
I am not aware of any Morrison manual,
but a Masport manual may help [attached].
Any images will help here.
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Jack