>>>Is it work saving.
Probably, that's a nice mower.
You can get an exploded view at www.boats.net, select Honda parts on the left, Lawnmower parts, then All Years. From the list select HR21 SXA LAWN MOWER, JPN, VIN# HR21-1000001 TO HR21-1051093 (I think the SXA and SXM are the same). Each breadown view has an orderable parts list and the parts for that mower are available.
For the Owners manual with maintenance info:
At: http://www.hondapowerequipment.com/products/manuals/Default.aspx
Select Lawnmowers then Other Lawn Mowers, which will give you a selectable list which has your mower.
The direct link is: http://www.hondapowerequipment.com/pdf/manuals/3195200.pdf