Small Engines (Lawn Mowers, etc.): 917.270821, set screws, set screw


Question
19.5 HP, 42" Craftsman tractor bought new in 1998.  Had a starting issue, but cleaned the carburetor and it started right up.  Now my problem is the tractor will not go forward or backward(reverse).  There seems to be noise when I depress the clutch, that does not sound normal.  Never have replaced 140294 "v-belt, ground drive."  Would replacing that solve this issue?  I cannot believe there is something wrong with the transmission.

Thank you for your time.

Answer
http://www.mymowerparts.com/pdf/Husqvarna_Parts_Manuals/I9801053.pdf
http://www.hydro-gear.com/Support/DealerLocator.aspx
http://www.hydro-gear.com/Support/YourProduct.aspx

Repair Manual  http://www.manuals.us/browseproducts/Hydro-Gear-310-0510-Hydro-Transaxle-service...

You have a Hydyo-Gear transaxle model 310-0650.  I searched the internet and found several sites that recommended changing the fluid.  

After you change the fluid you may have air in the system. To remove it jack up the drive wheels and start the engine. with the engine at idle move the controls to full forward for a few minutes and then full reverse for a few minutes. If a lot of air got trapped this could take up to half an hour to purge the system.

Did you check the set screw that holds the arm attached to the pump? I've had a few with loose set screws.

Tighten up the set screw and change the fluid to 20W50 synthetic fluid.

Do you have any experience with hydros?
Let me know.
Eric