AFAIK Massey Ferguson do not make the ZTR they are made by Briggs at one of the plants they took over.
The service manual is available from here
http://www.agcopubs.com/productpage.aspx?ProdIdentifier=4283357M91
At $ 100 it is not cheap but manuals from agricultural equipment companies are generally a cut above others and designed to be understood by 3rg generation farmers from families that "don't do book learnen".
The other alternative is to find a repair only workshop .
This time of year they will not be flat strap preparring mowers for sale so should have the time to sort your problem out.
And even then you might have to front up the cost of the manual.
If I was doing it I would have added at least 1/2 the cost of the manual in my service charge, particularly if i am unlikely to ever see one again.
Most farm equipment mechanics can fix a mower it is just an engine & hydraulic system but most wont touch one if they do not have the service information.
Alternatively buy the manual yourself, and post what you do not understand here .
Working from a manual on stuff we have never seen before is all in a days work for a lot of us on there so once we can see what we are working with most of the proceedures are the same.
For instance simple things like overfilling the hydraulics then leaving it for a few days to allow the air to bubble through, prefilling oil filters.
If a filter points down then it should be filled before replacing the filter.
Lift rams oft need to be bled so it is just a matter of opening the return line the running the lifter till oil comes out etc etc etc.