Hi,
Manuals for that machine may be hard to come by since it was last made 20 years ago. You can of course purchase one from Deere at:
John Deere Ag - New Equipment: Technical Publications - Publications Search (http://www.deere.com/en_US/ProductCatalog/HO/servlet/servlet/com.deere.u90785.cce.productcatalog.view.servlets. PublicationsListServlet?equipID=6284&language=english&searchCriteria=185&exactModelSearchFlag=off&orderBy=pubType&tM=HO)
For some info see:
TractorData.com John Deere 185 tractor information (http://www.tractordata.com/lawn-tractors/000/0/1/19-john-deere-185.html)
Or buy it here:
John Deere 185 Service, Repair & Owners Operators Manual Shop (http://www.ssbtractor.com/tractor_manual_search.cgi?tractor_manual_make=John +Deere&tractor_manual_model=185)
Prices can vary and you may wish to try Ebay.
Peace,
Clarke