Small Engines (Lawn Mowers, etc.): Peerless transmission - scotts mower, filler tube, dump valve

Question
My Scotts rider with a hydrostat transmission will not engage/move.  I believe that the model of the transmission is 6265-P1.  It was moving slower over time, all linkage is in place and operational, and appears to be working fine.  It acts like a filter is clogged or clutches are worn out...   Any suggestions?

Answer
Brian- first thing- check your drive belt.  If thats ok- not much a lay-person can do with these units (note* generally, unless they have a dump valve, you can't push a hydro transmission, even in neutral-they must be under power to move-valve is usually located on the side of the frame, under the edge of the seat).  Theres no user serviceable filters or even a fluid filler tube.

check that belt & lemme know!