With a 917. prefix to the model #, it's made by HOP, so the MTD books won't help him...There isn't one so you can stop looking
What problems do you have ?
MTD put out a series om manuals called
The Must Have manuas of Outdoor Power equipment
Volume 2 does ride ons pre 2002
IT is kicking around the web
A big book some 350 pages
While there have been some changes since 2002 most of what you need to know is in there .