BROKEN MOWER DECK BELT FOR 48 IN. CUT. REPLACEMENT DRIVE PATH AND TENSIONING DIAGRAM.

Do you mean the John Deere LT166 Lawn Tractor with 48" Convertible Deck mower. If so, the replacement belt is GX10063, according to the maintenance sheet: https://jdparts.deere.com/partsmkt/document/english/featbene/fb_MaintSheet_LT166_48CdeckLawnTractor.pdf . One vendor has the belt here: http://www.greenpartstore.com/John-Deere-Drive-Belt-GX10063.html .

I hope this helps. If you have a different mower deck, please add a comment with more information about your specific mower. I may be able to find additional JD parts for the machine. You can also look up parts here: http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.HomePageServlet_Alt .

Cindy Wells

You will need the model number to find this info. Usually on a plate or sticker under the seat. The use a parts site like jackssmallengines.com or simply Google your make and model followed by "deck belt"

Changing the Blade Drive Belts:
a.Set the parking brake. Remove ignition key and both spark plug caps.
b.Unscrew the wing nuts from the deck covers and remove both covers.
c.Using a 3/8" socket breaker bar or socket ratchet insert the drive end into the 3/8" square opening in the lower idler arm assembly and push the idler arm counterclockwise. While holding the idler arm back, loosen the blade drive belt from the pulley and slide the belt away from the pulley.
d.Remove tension of the PTO belt by moving the belt tensioning rod. Loosen the belt retaining bolt.
e.Pull the tensioner pulley away from the belt and remove the PTO belt then remove the blade drive belt.
f.Reverse the process to install the belt.

Since you mentioned "48-inch riding mower" let's assume your question is about the mower deck and not the overall mower or its main drive belt (if manual shift-on-the-fly model). If the belt burns that means it is running but slipping against something; or that the drive sheave us turning against an impeded belt. In the first case the belt will be burned along its length; in the second the burning will be occuring in one location(s) along the belt. In any case of belt slippage, check first that all tensioners (springs) are properly in place and not broken or fatigued and in need of replacement. The only other thing would be resistance to belt running, such as:
blade blockage; blade rotor resistance from lack of grease or ruined bearing in need of replacment; grass clogging on deck underside or under blade drive pulley on deck top side; a pully sheave out of round; an obstacle between belt and sheave that is preventing free turn of sheave and belt run; misrouted belt; an overstretched belt that cannot be sufficiently tensioned. Inspect and correct or replace as needed.

need model number of mower.

primary belt goes from the engine to the deck the secondary goes on the deck and connects the blades together

Hiand welcome to FixYa, I am Kelly

This is the deck routing diagram:
http://jdpc.deere.com/pimages/MP39/MP39302________UN29JAN07.gif

There are 3 models of the LA145. Hopefully this is the correct diagram. The deck belt routing appears to be the same on all 3 models.

Thanks for choosing FixYa,
Kelly

look under foot rest on tractor usually there is a diagram under there for belt routing and also sometimes on the mower deck it's self